Anti-diabetic properties of chrysophanol and its glucoside from rhubarb rhizome

2,3-Dihydrosorbicillin and chrysopanol stimulate insulin secretion in INS-1 cells

Pancreatic β-cell function and insulin secretion are important in antidiabetic drug development. In an effort to discover small molecules to regulate insulin secretion, an endophytic fungus, Penicillium sp. SSP-1CLG, was selected for chemical investigation. Large scale cultures of the strain followed by extraction and chromatographic analysis led to the isolation of 10 anthraquinone and alkaloid-type compounds. The isolated compounds were identified by comprehensive analysis of NMR, MS, and ECD data. The effect of compounds 1-10 on insulin secretion in INS-1 cells was investigated. 2,3-Dihydrosorbicillin (1), chrysophanol (2), and glandicolin B (10) at non-cytotoxic concentrations resulted in an increase of glucose-stimulated insulin secretion (GSIS) in rat INS-1 pancreatic β-cells. Furthermore, we investigated the signaling pathway involved in 2,3-dihydrosorbicillin (1) and chrysophanol (2) action in the activation of peroxisome proliferator-activated receptor γ (PPARγ), pancreatic and duodenal homeobox-1 (PDX-1), insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3-kinase (PI3K), and Akt. Treatment of INS-1 cells with 2,3-dihydrosorbicillin (1) and chrysophanol (2) increased the expression of these proteins. Our findings indicate that 2,3-dihydrosorbicillin and chrysophanol may play roles in the regulation of insulin secretion in pancreatic β-cells, at least in part, by targeting PPARγ and PDX-1 via the IRS-2/PI3K/Akt signaling pathway.

Chrysophanol prevents IL-1β-Induced inflammation and ECM degradation in osteoarthritis via the Sirt6/NF-κB and Nrf2/NF-κB axis

Osteoarthritis (OA) is a common joint illness that negatively impacts people's lives. The main active ingredient of cassia seed or rhubarb is chrysophanol. It has various pharmacological effects including anticancer, anti-diabetes and blood lipid regulation. Previous evidence suggests that chrysophanol has anti-inflammatory properties in various diseases, but its effect on OA has not been investigated yet. In this study, chrysophanol inhibited IL-1β -induced expression of ADAMTS-4, MMP13, COX-2 and iNOS. Meanwhile, it can inhibit aggrecan and collagen degradation in osteoarthritic chondrocytes induced by IL-1β.Further studies depicted that SIRT6 silencing eliminated the chrysophanol effect on IL-1β. The results demonstrated that chrysophanol could stimulate SIRT6 activation and, more importantly, increase SIRT6 levels. We also discovered that chrysophanol might impede the NF-κB pathway of OA mice's chondrocytes induced by IL-1β, which could be because it depends on SIRT6 activation to some extent. It had also been previously covered that chrysophanol could produce a marked effect on Nrf2/NF-κB axis [1]. Therefore, we can infer that chrysophanol may benefit chondrocytes by regulating the SIRT6/NF-κB and Nrf2/NF-κB signaling axis.We examined the anti-inflammatory mechanism and the impact of chrysophanol on mice in vitro and in vivo. In summary, we declare that chrysophanol diminishes the inflammatory reaction of OA in mice in vitro by regulating SIRT6/NF-κB and Nrf2/NF-κB signaling pathway and protects articular cartilage from degradation in vivo. We can infer that chrysophanol could be an efficient therapy for OA.

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.

Brevianthrones, bianthrones from a Chinese isolate of the endophytic fungus Colletotrichum brevisporum

Seven undescribed bianthrones, the brevianthrones, together with two known anthraquinones, were isolated from the plant-derived fungus Colletotrichum brevisporum, obtained from the plant Piper sarmentosum Roxb., collected in Guangxi, China. This is the first report of the isolation of bianthrones from the Colletotrichum genus. The structures of the compounds were elucidated by a combination of NMR and MS spectroscopic analysis, while the absolute configurations were determined by X-ray crystallography and by simulation of ECD spectra.

Gundelia tournefortii: Fractionation, Chemical Composition and GLUT4 Translocation Enhancement in Muscle Cell Line

Type 2 diabetes (T2D) is a chronic metabolic disease, which could affect the daily life of patients and increase their risk of developing other diseases. Synthetic anti-diabetic drugs usually show severe side effects. In the last few decades, plant-derived drugs have been intensively studied, particularly because of a rapid development of the instruments used in analytical chemistry. We tested the efficacy of Gundelia tournefortii L. (GT) in increasing the translocation of glucose transporter-4 (GLUT4) to the myocyte plasma membrane (PM), as a main strategy to manage T2D. In this study, GT methanol extract was sub-fractionated into 10 samples using flash chromatography. The toxicity of the fractions on L6 muscle cells, stably expressing GLUTmyc, was evaluated using the MTT assay. The efficacy with which GLUT4 was attached to the L6 PM was evaluated at non-toxic concentrations. Fraction 6 was the most effective, as it stimulated GLUT4 translocation in the absence and presence of insulin, 3.5 and 5.2 times (at 250 μg/mL), respectively. Fraction 1 and 3 showed no significant effects on GLUT4 translocation, while other fractions increased GLUT4 translocation up to 2.0 times. Gas chromatography-mass spectrometry of silylated fractions revealed 98 distinct compounds. Among those compounds, 25 were considered anti-diabetic and glucose disposal agents. These findings suggest that GT methanol sub-fractions exert an anti-diabetic effect by modulating GLUT4 translocation in L6 muscle cells, and indicate the potential of GT extracts as novel therapeutic agents for T2D.

Bioactive Agent Discovery from the Natural Compounds for the Treatment of Type 2 Diabetes Rat Model

Diabetes mellitus is a well-known chronic metabolic disease that poses a long-term threat to human health and is characterized by a relative or absolute lack of insulin, resulting in hyperglycemia. Type 2 diabetes mellitus (T2DM) typically affects many metabolic pathways, resulting in β-cell dysfunction, insulin resistance, abnormal blood glucose levels, inflammatory processes, excessive oxidative reactions, and impaired lipid metabolism. It also leads to diabetes-related complications in many organ systems. Antidiabetic drugs have been approved for the treatment of hyperglycemia in T2DM; these are beneficial for glucose metabolism and promote weight loss, but have the risk of side effects, such as nausea or an upset stomach. A wide range of active components, derived from medicinal plants, such as alkaloids, flavonoids, polyphenol, quinones, and terpenoids may act as alternative sources of antidiabetic agents. They are usually attributed to improvements in pancreatic function by increasing insulin secretions or by reducing the intestinal absorption of glucose. Ease of availability, low cost, least undesirable side effects, and powerful pharmacological actions make plant-based preparations the key player of all available treatments. Based on the study of therapeutic reagents in the pathogenesis of humans, we use the appropriate animal models of T2DM to evaluate medicinal plant treatments. Many of the rat models have characteristics similar to those in humans and have the advantages of ease of genetic manipulation, a short breeding span, and access to physiological and invasive testing. In this review, we summarize the pathophysiological status of T2DM rat models and focus on several bioactive compounds from herbal medicine with different functional groups that exhibit therapeutic potential in the T2DM rat models, in turn, may guide future approach in treating diabetes with natural drugs.

What we already know about rhubarb: a comprehensive review

Rhubarb (also named Rhei or Dahuang), one of the most ancient and important herbs in traditional Chinese medicine (TCM), belongs to the Rheum L. genus from the Polygonaceae family, and its application can be traced back to 270 BC in "Shen Nong Ben Cao Jing". Rhubarb has long been used as an antibacterial, anti-inflammatory, anti-fibrotic and anticancer medicine in China. However, for a variety of reasons, such as origin, variety and processing methods, there are differences in the effective components of rhubarb, which eventually lead to decreased quality and poor efficacy. Additionally, although some papers have reviewed the relationship between the active ingredients of rhubarb and pharmacologic actions, most studies have concentrated on one or several aspects, although there has been great progress in rhubarb research in recent years. Therefore, this review aims to summarize recent studies on the geographic distribution, taxonomic identification, pharmacology, clinical applications and safety issues related to rhubarb and provide insights into the further development and application of rhubarb in the future.

Chrysophanol Mitigates T Cell Activation by Regulating the Expression of CD40 Ligand in Activated T Cells

Since T lymphocytes act as mediators between innate and acquired immunity, playing a crucial role in chronic inflammation, regulation of T cell activation to suitable levels is important. Chrysophanol, a member of the anthraquinone family, is known to possess several bioactivities, including anti-microbial, anti-cancer, and hepatoprotective activities, however, little information is available on the inhibitory effects of chrysophanol on T cell activation. To elucidate whether chrysophanol regulates the activity of T cells, IL-2 expression in activated Jurkat T cells pretreated with chrysophanol was assessed. We showed that chrysophanol is not cytotoxic to Jurkat T cells under culture conditions using RPMI (Rosewell Park Memorial Institute) medium. Pretreatment with chrysophanol inhibited IL-2 production in T cells stimulated by CD3/28 antibodies or SEE-loaded Raji B cells. We also demonstrated that chrysophanol suppressed the expression of the CD40 ligand (CD40L) in activated T cells, and uncontrolled conjugation between B cells by pretreatment with chrysophanol reduced T cell activation. Besides, treatment with chrysophanol of Jurkat T cells blocked the NFκB signaling pathway, resulting in the abrogation of MAPK (mitogen-activated protein kinase) in activated T cells. These results provide novel insights into the suppressive effect of chrysophanol on T cell activation through the regulation of CD40L expression in T cell receptor-mediated stimulation conditions.

Chrysophanol ameliorates renal interstitial fibrosis by inhibiting the TGF-β/Smad signaling pathway

Renal interstitial fibrosis (RIF) is a major pathological feature of chronic kidney disease at middle and end stages. Chrysophanol (CP), 1,8-dihydroxy-3-methyl-9,10-anthraquinone, is an anthraquinone isolated from Rheum palmatum L. with a variety of pharmacological activities including the suppression of RIF. However, the effect of CP on renal fibrosis and its potential mechanism have not been elucidated. We conducted a comprehensive study by determining the expression levels of fibrotic markers and proteins including TGF-β1, α-SMA, and Smad3 related to transforming growth factor-beta/Smad (TGF-β/Smad) pathway in unilateral ureteral obstruction (UUO) mice and TGF-β1-stimulated HK-2 cells with the treatment of CP using western blotting and RT-qPCR analyses. Using small interfering RNA and co-immunoprecipitation, we evaluated the influences of CP on the interactions between Smad3 and Smad7 proteins and also on TGF-β RI and TGF-βR II. We found that CP administration significantly ameliorated UUO-induced kidney damage by reversing abnormal serum and urine biochemical parameters and decreasing the production of fibrotic markers including collagen I, collagen III, fibronectin, and α-SMA. Our results showed that TGF-β1 and phospho-Smad3 (p-Smad3) expression was significantly down-regulated and Smad7 expression was up-regulated by CP in UUO mice compared to the model group; however, the expression of Smad2, Smad4, and TGF-β receptors was not affected. Furthermore, CP modulated these fibrotic markers as well as p-Smad3 and Smad7 in TGF-β1-induced HK-2 cells. The inhibitory effect of CP was markedly reduced in TGF-β1-treated HK-2 cells transfected with Smad3 siRNA. Additionally, co-immunoprecipitation analysis indicated that CP blocked the interaction between Smad3 and TGF-β receptor I to suppress p-Smad3 expression. These findings demonstrated that CP alleviated RIF by inhibiting Smad3 phosphorylation, which provides a molecular basis for a new drug candidate for the treatment of RIF.

The pharmacological properties of chrysophanol, the recent advances

As a universal Chinese medicine, Rhei Radix et Rhizoma was used for centuries in different fields including pharmaceutical, health care and cosmetics. Chrysophanol (Chr) is one of the most important anthraquinone components isolated from plants of the Rheum genus. Current reports show that in Rheum officinale, Chr is the most abundant free anthraquinone compound [1] and exerts a number of beneficial effects, such as anti-inflammation, anti-cancer, and anti-depressive effects and offers neuroprotection. We collected information about Chr from the Internet databases PubMed, Web of Science, Europe PMC and CNKI with a combination of keywords including "Chr", "Pharmacology", and "Pharmacokinetics". All data about this ingredient in this review were extracted from articles published before September 2019. Based on the literature found, we concluded that (1) Chr exhibited potential anti-inflammation, anti-cardiovascular disease (CVD)and anti-cancer activities by regulating signaling pathway transduction (NF-κB, MAPK, PI3K/Akt, etc.); (2) compared with free Chr, pharmacokinetic studies revealed that other forms of Chr, such as nanoparticle-based and liposome-based Chr, showed high bioavailability. Nevertheless, we also found that the understanding of the exact differences in the regulation of multiple molecular signaling pathways is in a preliminary stage and needs to be clarified. Moreover, further studies are required to determine the apoptotic mechanism of Chr in cancer cells. Finally, we found that (3) structure modification studies demonstrated potential relationships between structure and drug activity. The purpose of this review is to summarize the pharmacological activities, intracorporal processes and structure-activity relationships of Chr and to provide an up-to-date reference for further research and clinical applications.

Chrysophanol: a review of its pharmacology, toxicity and pharmacokinetics

OBJECTIVE

Chrysophanol is a natural anthraquinone, also known as chrysophanic acid and 1,8-dihydroxy-3-methyl-anthraquinone. It has been widely used in the food and pharmaceutical fields. This review is intended to provide a comprehensive overview of the pharmacology, toxicity and pharmacokinetic researches of chrysophanol.

KEY FINDING

Information on chrysophanol was collected from the Internet database PubMed, Elsevier, ResearchGate, Web of Science, Wiley Online Library and Europe PM using a combination of keywords including 'pharmacology', 'toxicology' and 'pharmacokinetics'. The literature we collected included from January 2010 to June 2019. Chrysophanol has a wide spectrum of pharmacological effects, including anticancer, antioxidation, neuroprotection, antibacterial and antiviral, and regulating blood lipids. However, chrysophanol has obvious hepatotoxicity and nephrotoxicity, and pharmacokinetics indicate that the use of chrysophanol in combination with other drugs can reduce toxicity and enhance efficacy.

SUMMARY

Chrysophanol can be used in many diseases. Future research directions include how the concentration of chrysophanol affects pharmacological effects and toxicity; the mechanism of synergy between chrysophanol and other drugs.

Chrysophanol protects against doxorubicin-induced cardiotoxicity by suppressing cellular PARylation

The clinical application of doxorubicin (DOX) in cancer chemotherapy is limited by its life-threatening cardiotoxic effects. Chrysophanol (CHR), an anthraquinone compound isolated from the rhizome of Rheum palmatum L., is considered to play a broad role in a variety of biological processes. However, the effects of CHR׳s cardioprotection in DOX-induced cardiomyopathy is poorly understood. In this study, we found that the cardiac apoptosis, mitochondrial injury and cellular PARylation levels were significantly increased in H9C2 cells treated by Dox, while these effects were suppressed by CHR. Similar results were observed when PARP1 activity was suppressed by its inhibitors 3-aminobenzamide (3AB) and ABT888. Ectopic expression of PARP1 effectively blocked this CHR׳s cardioprotection against DOX-induced cardiomyocyte injury in H9C2 cells. Furthermore, pre-administration with both CHR and 3AB relieved DOX-induced cardiac apoptosis, mitochondrial impairment and heart dysfunction in Sprague-Dawley rat model. These results revealed that CHR protects against DOX-induced cardiotoxicity by suppressing cellular PARylation and provided critical evidence that PARylation may be a novel target for DOX-induced cardiomyopathy.

In Vitro Anticancer MCF-7, Anti-Inflammatory, and Brine Shrimp Lethality Assay (BSLA) and GC-MS Analysis of Whole Plant Butanol Fraction of Rheum ribes (WBFRR)

In this study, GC-MS analysis has shown that whole plant butanol fraction of rheum ribes (WBFRR) comprises of 21 compounds which exhibited anticancer (MCF-7) activity having IC50 value of 36.01± 0.26. MTT assay (MCF-7), Oxidative Burst assay using chemiluminescence technique, and B-Hatching techniques were the methods used for anticancer MCF-7, anti-inflammatory, and Brine Shrimp Lethality Assay (BSLA). GC-MS was used for structural elucidation. Whole plant methanol extract of rheum ribes (WMERR), whole plant n-hexane fraction of rheum ribes (WHFRR), and whole plant aqueous fraction of rheum ribes (WAFRR) were inactive against anticancer (MCF-7) cell line. Whole plant methanol extract of rheum ribes (WMERR), whole plant aqueous fraction of rheum ribes (WAFRR) and whole plant butanol fraction of rheum ribes (WBFRR) showed anti-inflammatory activity on ROS having IC50 value of 23.2±1.9, 24.2±2.7 and 12.0±0.6. Whole plant butanol fraction of rheum ribes (WBFRR) showed Brine Shrimp Lethality with LD50 693.302 while whole plant methanol extract of rheum ribes (WMERR) and whole plant aqueous fraction of rheum ribes (WAFRR) showed high lethality at highest concentration. This study revealed that whole plant butanol fraction of rheum ribes (WBFRR) exhibited significant anticancer (MCF-7) activity. In the near future, the constituent of whole plant butanol fraction of rheum ribes (WBFRR) can be the alternative drug against MCF-7 cell line with least toxicity and side effects.

Pharmacological properties of Rheum turkestanicum Janisch

Medicinal herbs have been increasingly used worldwide for diseases prevention and treatment. Rheum turkestanicum Janisch. is a perennial shrub of the Polygonaceae family. Genus Rheum includes more than 60 species growing around the world which are used in foods and traditional medicines. R. turkestanicum is believed to be able to improve different kinds of disorders including diabetes, hypertension, jaundice and cancer. In recent years, this medicinal plant has been a subject of many experimental studies to document its health-beneficial properties. These studies have revealed antidiabetic, anticancer, nephroprotective, cardioprotective, and hepatoprotective properties of R. turkestanicum. The presence of flavonoids (e.g. epicatechin and quercetin) and anthraquinones (e.g. chrysophanol, physcion, and emodin) in R. turkestanicum justifies its health-beneficial effects. Nevertheless, possible therapeutic applications and safety of this plant still need to be elucidated in further clinical studies.

Annona stenophylla aqueous extract stimulate glucose uptake in established C2Cl2 muscle cell lines

BACKGROUND

Annona stenophylla is a folk medicine popularly used in Zimbabwe for the treatment of many ailments. This study was carried out to determine some of the possible anti diabetic mechanisms of its action using in vitro cell culturing methods.

METHODS

A. stenophylla's effects on glucose uptake were tested using muscle cells (C2Cl2). Expression of glucose 4 transporters was determined by treating cell lines with plant extract. Total RNA was isolated and using RT-PCR, GLUT 4 expression levels were quantified. Translocation of GLUT 4 was assessed using FITC fluorescence measured by flow cytometry.

RESULTS

Treatment of cells with plant extract significantly increased glucose uptake in a concentration dependent manner, with the highest concentration (250 µg/ml) giving 28% increased uptake compared to the negative control. The increase in glucose uptake (2.5 times more than control) was coupled to increase in GLUT 4 mRNA and subsequently GLUT 4 translocation. Wortmannin expunged the A. stenophylla induced increase in GLUT 4 mRNA and glucose uptake.

CONCLUSION

The results suggest that A. stenophylla aqueous extract increases glucose uptake partly through increasing the GLUT 4 mRNA and translocation potentially acting via the PI-3-K pathway. This study confirms the ethnopharmacological uses of A. stenophylla indicating potential for anti-diabetic products formulation.

Chrysophanol attenuated isoproterenol-induced cardiac hypertrophy by inhibiting Janus kinase 2/signal transducer and activator of transcription 3 signaling pathway

Cardiac hypertrophy is a common pathological change found in various cardiovascular diseases. Although it has long been recognized as an important risk factor responsible for heart failure, there is still a lack of effective treatments in clinic. Chrysophanol is a natural compound with multiple biological activities and protective roles in the cardiovascular system. However, its potential effect on cardiac hypertrophy remains unclear. In the current study, we found that chrysophanol could protect against isoproterenol (ISO)-induced cardiac hypertrophy both in vitro and in vivo. Increase of cell surface and hypertrophic marker expression induced by ISO in neonatal rat cardiomyocytes was downregulated by chrysophanol. Moreover, chrysophanol ameliorated the abnormal changes of cardiac structure and function in rats subjected to ISO injection, as shown by echocardiography and morphometry measurements. Further mechanistical investigation demonstrated that chrysophanol inhibited phosphorylation of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) induced by ISO. Nuclear translocation of STAT3 and transcription of downstream genes promoted by ISO treatment were also remarkably suppressed by chrysophanol. Taken together, our findings revealed that chrysophanol attenuated ISO-induced cardiac hypertrophy by inhibiting JAK2/STAT3 signaling pathway. Chrysophanol may be a potential candidate compound for the prevention and treatment of hypertrophy-related cardiomyopathy.

Jinmaitong, a Traditional Chinese Compound Prescription, Ameliorates the Streptozocin-Induced Diabetic Peripheral Neuropathy Rats by Increasing Sciatic Nerve IGF-1 and IGF-1R Expression

Jinmaitong (JMT) is a Traditional Chinese Compound Prescription for the treatment of diabetic peripheral neuropathy (DPN). This study aims to investigate the effect of JMT on the insulin-like growth factor 1 (IGF-1) and the insulin like growth factor 1 receptor (IGF-1R) expression in sciatic nerves of diabetic rats. Firstly, the chemical profile of JMT was characterized by UPLC/Q-TOF-MS analysis. A total of 72 compounds were putatively identified. Secondly, streptozotocin (STZ)-induced diabetic rats were treated with neurotropin (NTP, 2.67 NU/kg/day) or JMT at low-dosage (0.4375 g/kg/day), medium-dosage (0.875 g/kg/day), and high-dosage (1.75 g/kg/day) for continuous 16 weeks. Blood glucose and body weight were detected every 4 weeks during the experiment. The mechanical pain and morphological change on sciatic nerves were detected by pain measurement instrument and microscopy. The IGF-1 level in serum and tissues were measured though ELISA and immunohistochemistry. The mRNA and protein expressions of IGF-1, IGF-1R, peripheral myelin protein zero (P0), and peripheral myelin protein 22 (PMP22) in the tissues were measured by qRT-PCR and western blot. As a result, JMT had no significant effect on body weight, but reduced the fasting blood glucose levels of diabetic rats. Besides, the pathological morphology, mechanical pain thresholds, serum level and tissue expression of IGF-1, mRNA, and protein levels of IGF-1R, P0, and PMP22 were significantly improved in JMT group at middle dosage. In conclusion, JMT could ameliorate the behavioristics and morphology changes in DPN rats by promoting IGF-1 and IGF-1R gene and protein expressions in sciatic nerves, as well as regulating the peripheral nerve remyelination genes P0 and PMP22 expressions, which provides scientific evidence for the clinical application of JMT in DPN patients.

Chrysophanol: A Natural Anthraquinone with Multifaceted Biotherapeutic Potential

Chrysophanol is a unique anthraquinone having broad-spectrum therapeutic potential along with ecological importance. It is the first polyketide that has been reported to be biosynthesized in an organism-specific manner. The traditional Chinese and Korean medicinal systems provide evidence of the beneficial effects of chrysophanol on human health. The global distribution of chrysophanol encountered in two domains of life (bacteria and eukaryota) has motivated researchers to critically evaluate the properties of this compound. A plethora of literature is available on the pharmacological properties of chrysophanol, which include anticancer, hepatoprotective, neuroprotective, anti-inflammatory, antiulcer, and antimicrobial activities. However, the pharmacokinetics and toxicity studies on chrysophanol demand further investigations for it to be used as a drug. This is the first comprehensive review on the natural sources, biosynthetic pathways, and pharmacology of chrysophanol. Here we reviewed recent advancements made on the pharmacokinetics of the chrysophanol. Additionally, we have highlighted the knowledge gaps of its mechanism of action against diseases and toxicity aspects.

A Cell-Based Metabonomics Approach to Investigate the Varied Influences of Chrysophanol-8-O-β-D-Glucoside With Different Concentrations on L-02 Cells

In this study, the effects of different concentrations of chrysophanol-8-O-β-D-glucoside (C-8-O-β-D-glu) on L-02 liver cells were analyzed by high content analysis (HCA) and metabonomics to explore the potential mechanism involved. The results showed that low concentrations (12 and 24 μM) of C-8-O-β-D-glu increased the cells viability significantly, while high concentration (96 μM) showed significant cytotoxicity on L-02 cells. HCA was applied to analyze the changes of nuclei and mitochondria after the cells being exposed to C-8-O-β-D-glu for 24 h. The results showed high concentration (96 μM) of C-8-O-β-D-glu significantly reduced the number of living cells, increased average nucleus area, DNA content and mitochondrial membrane potential (MMP). Then non-target metabonomics was carried out to identify potential biomarkers and metabolic pathways of L-02 cells impacted by C-8-O-β-D-glu. Eleven important potential biomarkers associated with four metabolic pathways were identified in this analysis. Dysregulation of alanine, aspartate and glutamate metabolism were observed in both LCG and HCG. In addition, low concentration (24 μM) of C-8-O-β-D-glu would impact arginine and proline metabolism. High concentration (96 μM) of C-8-O-β-D-glu would impact phenylalanine metabolism and beta-alanine metabolism. Alanine, aspartate and glutamate metabolism, arginine and proline metabolism, phenylalanine metabolism, beta-alanine metabolism were involved in different effects of C-8-O-β-D-glu on L-02 cells.

Anti-hyperglycemic and genotoxic studies of 1-O-methyl chrysophanol, a new anthraquinone isolated from Amycolatopsis thermoflava strain SFMA-103

The compound 1-O-methyl chrysophanol (OMC) which belongs to a class of hydroxyanthraquinones was isolated from Amycolatopsis thermoflava strain SFMA-103 and studied for their anti-diabetic properties. OMC was evaluated as an anti-diabetic agent based on in silico studies which initially predicted the binding energy with α-amylase (-188.81 KJ mol^-1) and with α-glucosidase (70.53 KJ mol^-1). Further, these results were validated based on enzyme inhibition assays where OMC demonstrated enzyme inhibitory activity towards α-amylase (IC₅₀ 3.4 mg mL^-1) and α-glucosidase (IC₅₀ 38.49 μg mL^-1). To confirm the anti-diabetic activity, in vivo studies (oral dose in Wistar rats) revealed that OMC inhibited significantly the increase in glucose concentration at 100 mg/kg as compared to starch control (p < 0.05). Further, to understand the safety of OMC as a therapeutic agent, the genotoxic analysis was performed in both in vitro Chinese Hamster Ovary cells (250, 500, and 1000 µM/mL) and in vivo Swiss albino mice (250, 500, and 1000 mg/kg). In vitro results showed that OMC concentration of up to 250 µM/mL did not elicit significant changes in CAs, MI, and MN counts in CHO cells. Similarly, in mice experiments (i.p. injection), no significant changes in CAs, MI, and MN induction were observed till 500 mg/kg of OMC when compared with chrysophanic acid (Cy) (200 mg/kg). In addition, mice that received the lowest dose of OMC (250 mg/kg) did not show any histological changes in liver, kidney, and heart. The study concluded that five times higher therapeutic dose (100 mg/kg) of OMC can be utilized against hyperglycemia with no genotoxic effects.

Ethanolic Extract of Folium Sennae Mediates the Glucose Uptake of L6 Cells by GLUT4 and Ca2

In today’s world, diabetes mellitus (DM) is on the rise, especially type 2 diabetes mellitus (T2DM), which is characterized by insulin resistance. T2DM has high morbidity, and therapies with natural products have attracted much attention in the recent past. In this paper, we aimed to study the hypoglycemic effect and the mechanism of an ethanolic extract of Folium Sennae (FSE) on L6 cells. The glucose uptake of L6 cells was investigated using a glucose assay kit. We studied glucose transporter 4 (GLUT4) expression and AMP-activated protein kinase (AMPK), protein kinase B (PKB/Akt), and protein kinase C (PKC) phosphorylation levels using western blot analysis. GLUT4 trafficking and intracellular Ca²⁺ levels were monitored by laser confocal microscopy in L6 cells stably expressing IRAP-mOrange. GLUT4 fusion with plasma membrane (PM) was observed by myc-GLUT4-mOrange. FSE stimulated glucose uptake; GLUT4 expression and translocation; PM fusion; intracellular Ca²⁺ elevation; and the phosphorylation of AMPK, Akt, and PKC in L6 cells. GLUT4 translocation was weakened by the AMPK inhibitor compound C, PI3K inhibitor Wortmannin, PKC inhibitor Gö6983, G protein inhibitor PTX/Gallein, and PLC inhibitor U73122. Similarly, in addition to PTX/Gallein and U73122, the IP3R inhibitor 2-APB and a 0 mM Ca²⁺-EGTA solution partially inhibited the elevation of intracellular Ca²⁺ levels. BAPTA-AM had a significant inhibitory effect on FSE-mediated GLUT4 activities. In summary, FSE regulates GLUT4 expression and translocation by activating the AMPK, PI3K/Akt, and G protein–PLC–PKC pathways. FSE causes increasing Ca²⁺ concentration to complete the fusion of GLUT4 vesicles with PM, allowing glucose uptake. Therefore, FSE may be a potential drug for improving T2DM.

Cytochrome P450 mediated metabolic activation of chrysophanol

Chrysophanol, a major anthraquinone component occurring in many traditional Chinese herbs, is accepted as important active component with various pharmacological actions such as antibacterial and anticancer activity. Previous studies demonstrated that exposure to chrysophanol induced cytotoxicity, but the mechanisms of the toxic effects remain unknown. In the present metabolism study, three oxidative metabolites (M1-M3, aloe-emodine, 7-hydroxychrysophanol, and 2-hydroxychrysophanol) and five GSH conjugates (M4-M8) were detected in rat and human liver microsomal incubations of chrysophanol supplemented with GSH, and the formation of the metabolites was NADPH dependent except M4 and M5. M4 and M5 were directly derived from parent compound chrysophanol, M6 arose from M2, and M7 and M8 resulted from the oxidation of M4 and M5. Metabolites M5 and M6 were also observed in bile of rats after exposure to chrysophanol, M1-M3 and one NAC conjugate (M9) were detected in urine of rats administrated chrysophanol, and urinary metabolite M9 originated from the degradation of biliary GSH conjugation M6. Recombinant P450 enzyme incubation and microsome inhibition studies demonstrated that P450 1A2 was the primary enzyme responsible for the metabolic activation of chrysophanol and that P450 2B6 and P450 3A4 also participated in the generation of the oxidative metabolites. These findings helped us to understand the mechanisms of chrysophanol-induced cytotoxicity.

Natural products for the treatment of type 2 diabetes mellitus: Pharmacology and mechanisms

Epidemiological studies have implied that diabetes mellitus (DM) will become an epidemic accompany with metabolic and endocrine disorders worldwide. Most of DM patients are affected by type 2 diabetes mellitus (T2DM) with insulin resistance and insulin secretion defect. Generally, the strategies to treat T2DM are diet control, moderate exercise, hypoglycemic and lipid-lowing agents. Despite the therapeutic benefits for the treatment of T2DM, most of the drugs can produce some undesirable side effects. Considering the pathogenesis of T2DM, natural products (NPs) have become the important resources of bioactive agents for anti-T2DM drug discovery. Recently, more and more natural components have been elucidated to possess anti-T2DM properties, and many efforts have been carried out to elucidate the possible mechanisms. The aim of this paper was to overview the activities and underlying mechanisms of NPs against T2DM. Developments of anti-T2DM agents will be greatly promoted with the increasing comprehensions of NPs for their multiple regulating effects on various targets and signal pathways.

Synthesis of α-glycosidase hybrid nano-flowers and their application for enriching and screening α-glycosidase inhibitors

To rapidly and accurately screen compounds present in traditional Chinese herbal medicines for α-glycosidase inhibitors, we synthesized a novel nano-affinity material to enable the targeted screening of α-glycosidase inhibitors.

Identification and evaluation of magnolol and chrysophanol as the principle protein tyrosine phosphatase-1B inhibitory compounds in a Kampo medicine, Masiningan

ETHNOPHARMACOLOGICAL RELEVANCE

Masiningan is a traditional medicine consisting of six crude drugs that have been used for treating constipation and diabetes mellitus in both Japan and China. Masiningan has been reported to have significant PTP1B inhibitory activity and to affect cells in the insulin-signaling pathway. The aim of the present study is to identify the PTP1B inhibitory compounds in Masiningan.

MATERIALS AND METHODS

Bioactivity peaks were identified by analytical HPLC profiling and PTP1B inhibitory activity profiling of sub-fractions from Masiningan extract. The bioactive compounds were isolated by tracking two identified bioactive peaks, and the chemical structures were determined by spectroscopic analyses. The bioactive compounds were further investigated for their inhibitory effect against PTP1B by enzymatic kinetic analysis, molecular docking simulation, inhibitory selectivity against other PTPs, and cellular activity in the insulin signal transduction pathway.

RESULTS

From Masiningan, magnolol (1) and chrysophanol (2) were isolated as compounds that exhibited significant dose-dependent inhibitory activities against PTP1B, with IC50 values of 24.6 and 12.3μM, respectively. Kinetic analysis revealed that 1 is a non-competitive and that 2 is a competitive PTP1B inhibitor. In the molecular docking simulation, compound 2 was stably positioned in the active pocket of PTP1B, and the CDOCKER energy was calculated to be 24.3411kcal/mol. Both compounds demonstrated remarkably high selectivity against four PTPs and revealed cellular activity against the insulin signal transduction pathway.

CONCLUSIONS

Magnolol (1) and chrysophanol (2) were identified as the principle PTP1B inhibitory active compounds in Masiningan, and their actions were investigated in detail. These findings demonstrated the effectiveness of Masiningan on diabetes mellitus through the inhibition of PTP1B at a molecular level as well as the potential of magnolol (1) and chrysophanol (2) as lead compounds in future anti-diabetes drug development.

Influence of the Environmental Factors on the Accumulation of the Bioactive Ingredients in Chinese Rhubarb Products

To provide a basis for controlling the quality of rhubarb under artificial cultivation, the present work was designed to evaluate the contents of 14 active pharmaceutical ingredients (API) of rhubarb in major rhubarb production areas in China and analyze the correlations between the contents of API and such factors as species, geographic distribution and soil. The levels of fourteen API in rhubarb were measured using HPLC. The geographic distributions were collected using GPS and the nutrients in the soil were measured using the methods in the literature. The results showed that the levels of major API vary significantly among plants of different locations according to variance analysis. The species factor has few obvious effect on the overall properties of the rhubarb by the cluster analysis because of the two source species occurring in all divided three groups. However, Rheum tanguticum Maxim.ex Balf. is less effective at synthesizing and accumulating 9 API out of 14 than Rheum palmatum L. The correlation analysis and regression analysis also indicated that a lower latitude should be considered in the accumulation of API and a lower longitude should be considered to produce more compound anthraquinones. Lower levels of total P, rapidly available P and available molybdenum (Mo) and higher available K and available Zn in the soil were significantly correlated to accumulation of API in rhubarb. These results provide a basis for the clinical application and controlling the levels of the major API of rhubarb during artificial cultivation.

Protective effect of chrysophanol on LPS/d-GalN-induced hepatic injury through the RIP140/NF-κB pathway

Chrysophanol prevented LPS/d-GalN-induced liver injury through the induction of antioxidant defence, suppression of apoptosis and reduction of inflammatory response via inhibition of the RIP140/NF-κB pathway.

Clinical efficacy of 'Spleen-kidney-care' Yiqi Huayu and Jiangzhuo traditional Chinese medicine for the treatment of patients with diabetic nephropathy

The aim of the present study was to investigate the effect of the traditional Chinese medicine (TCM), 'Spleen-kidney-care' Yiqi Huayu and Jiangzhuo decoction (SKC-YJ), as an adjuvant therapy in diabetic nephropathy (DN) treatment. In total, 72 patients with DN were randomly divided into control (n=54) and experimental (n=18) groups, with the latter administered SKC-YJ treatment. Indicators for determining the condition of the patients included the levels of proteinuria, blood glucose, glycosylated hemoglobin, blood lipids, blood viscosity and C-reactive protein, which were used to analyze the treatment protocols for DN. Following SKC-YJ treatment, the urinary albumin excretion rate, fasting blood glucose, 2 h-postprandial blood glucose, glycosylated hemoglobin, triglyceride, total cholesterol, blood viscosity, fibrinogen and C-reactive protein levels were detected in the two groups, and were all demonstrated to decrease significantly following treatment with SKC-YJ. Furthermore, the results revealed that SKC-YJ treatment exhibited no significant side-effects on the blood, liver and renal functions or gastrointestinal reactions. By contrast, SKC-YJ improved the symptoms of nausea, vomiting and diarrhea in the patients with DN, while showing no allergic reaction during the observation period. Therefore, SKC-YJ treatment was shown to significantly improve the clinical efficacy of DN treatment, illustrating novel roles for TCM in DN treatment.

Virtualizing the p-ANAPL library: a step towards drug discovery from African medicinal plants

Background

Natural products play a key role in drug discovery programs, both serving as drugs and as templates for the synthesis of drugs, even though the quantities and availabilities of samples for screening are often limitted.

Experimental approach

A current collection of physical samples of > 500 compound derived from African medicinal plants aimed at screening for drug discovery has been made by donations from several researchers from across the continent to be directly available for drug discovery programs. A virtual library of 3D structures of compounds has been generated and Lipinski’s “Rule of Five” has been used to evaluate likely oral availability of the samples.

Results

A majority of the compound samples are made of flavonoids and about two thirds (2/3) are compliant to the “Rule of Five”. The pharmacological profiles of thirty six (36) selected compounds in the collection have been discussed.

Conclusions and implications

The p-ANAPL library is the largest physical collection of natural products derived from African medicinal plants directly available for screening purposes. The virtual library is also available and could be employed in virtual screening campaigns.

Quantifying four-probe metabolites in a single UPLC–MS/MS run to explore the effects of cooked rhubarb on cytochrome P450 isozymes

Background: Cytochrome P450 (CYP) enzymes primarily account for the oxidation of xenobiotics. A single run UPLC–MS/MS method was developed to simultaneously detect four metabolites from a probe cocktail to investigate four CYP isozymes. Paracetamol was detected to investigate CYP1A2, 4-hydroxytolbutamide for CYP2C6, 6-hydroxychlorzoxazone for CYP2E1 and dehydronifedipine for CYP3A1. 6-hydroxychlorzoxazone was detected in ESI-negative mode, while the other three were detected in ESI-positive mode. Results: The method was rapid (2.5 min) and validated to be specific, accurate and precise. It was successfully applied to evaluate the effects of cooked rhubarb on the activities of the four isozymes in rat microsomes. Cooked rhubarb inhibited the activity of CYP2C6 but induced both CYP2E1 and CYP3A1. Conclusion: This convenient UPLC–MS/MS method was applicable. It could improve the efficiency of future studies estimating the influence of herbs, herbal products or drug entities on the activities of CYP1A2, CYP2C6, CYP2E1 and CYP3A1.

Anticancer potential of emodin

Traditional Chinese Medicine (TCM) is widely used in clinical research due to its low toxicity, low number of side effects, and low cost. Many components of common fruits and vegetables play well-documented roles as chemopreventive or chemotherapeutic agents that suppress tumorigenesis. Anthraquinones are commonly extracted from the Polygonaceae family of plants, e.g., Rheum palmatum and Rheum officinale. Some of the major chemical components of anthraquinone and its derivatives, such as aloe-emodin, danthron, emodin, chrysophanol, physcion, and rhein, have demonstrated potential anticancer properties. This review evaluates the pharmacological effects of emodin, a major component of Aloe vera. In particular, emodin demonstrates anti-neoplastic, anti-inflammatory, anti-angiogenesis, and toxicological potential for use in pharmacology, both in vitro and in vivo. Emodin demonstrates cytotoxic effects (e.g., cell death) through the arrest of the cell cycle and the induction of apoptosis in cancer cells. The overall molecular mechanisms of emodin include cell cycle arrest, apoptosis, and the promotion of the expression of hypoxia-inducible factor 1α, glutathione S-transferase P, N-acetyltransferase, and glutathione phase I and II detoxification enzymes while inhibiting angiogenesis, invasion, migration, chemical-induced carcinogen-DNA adduct formation, HER2/neu, CKII kinase, and p34cdc2 kinase in human cancer cells. Hopefully, this summary will provide information regarding the actions of emodin in cancer cells and broaden the application potential of chemotherapy to additional cancer patients in the future.

Active ingredients of traditional Chinese medicine in the treatment of diabetes and diabetic complications

INTRODUCTION

Diabetes mellitus (DM) is a chronic progressive systemic disease caused by metabolic disorder. In recent years, significant amounts of studies have shown that traditional Chinese medicine (TCM) and its active ingredients have obvious hypoglycemic effect.

AREAS COVERED

This paper summarizes single herbs and their active ingredients from TCM with the role of treating DM, and relevant literatures published in the past decades are reviewed. The active ingredients are divided into polysaccharides, saponins, alkaloids, flavonoids, terpenoids and others, which are described in this article from the aspects of active ingredients, sources, models, efficacy, and mechanisms.

EXPERT OPINION

Mechanisms of TCM in treating DM are concluded: i) to promote insulin secretion and increase serum insulin levels; ii) to increase the sensitivity of insulin and improve its resistance; iii) to inhibit glucose absorption; iv) to affect glucose metabolism of insulin receptor; and v) to scavenge radicals and prevent lipid peroxidation. The separation and extraction of effective monomer from TCM is an important direction of anti-diabetic drug discovery currently. Future research about hypoglycemic mechanism of TCM based on the clinical should combine with modern scientific methods and regulatory approach to strive for more meaningful discovery and innovation.

Chrysophanol-8-O-glucoside, an anthraquinone derivative in rhubarb, has antiplatelet and anticoagulant activities

Rhubarb is a widely used traditional medicine and has been reported to elicit a number of biological effects including anti-inflammatory and antiplatelet effects. In the present study, we investigated the effects of anthraquinone derivatives isolated from rhubarb on platelet activity. Of four anthraquinone derivatives isolated from rhubarb examined, chrysophanol-8-O-glucoside (CP-8-O-glc) was found to have the most potent inhibitory effect on collagen- and thrombin-induced platelet aggregation. CP-8-O-glc-treated mice showed significantly prolonged bleeding times. Furthermore, CP-8-O-glc was found to have a significant inhibitory effect on rat platelet aggregation ex vivo and on thromboxane A(2) formation in vitro. In coagulation tests, CP-8-O-glc did not alter prothrombin time, and it prolonged the activated partial thromboplastin time. However, CP-8-O-glc only inhibited platelet phosphatidylserine exposure, but not exert direct inhibition on intrinsic factors. This study demonstrates the antiplatelet and anticoagulant effects of CP-8-O-glc and suggests that this compound might be of therapeutic benefit for the prevention of platelet-related cardiovascular diseases.