Evaluation of Rhubarb using antioxidative activity as an index of pharmacological usefulness

Ethnobotany and phytochemistry of plants used to treat musculoskeletal disorders among Skaw Karen, Thailand

CONTEXT

Musculoskeletal system disorders (MSD) are prevalent around the world affecting the health of people, especially farmers who work hard in the field. Karen farmers use many medicinal plants to treat MSD.

OBJECTIVE

This study collects traditional plant-based remedies used by the Skaw Karen to treat MSD and evaluates their active phytochemical compounds.

MATERIALS AND METHODS

The ethnobotanical study was conducted in six Karen villages in Chiang Mai province using semi-structured interviews were of 120 informants. The data were analyzed using ethnobotanical indices including use values (UV), choice value (CV), and informant consensus factor (ICF). Consequently, the 20 most important species, according to the indices, were selected for phytochemical analysis using LC-MS/MS.

RESULTS

A total of 3731 use reports were obtained for 139 species used in MSD treatment. The most common ailments treated with those plants were muscular pain. A total of 172 high-potential active compounds for MSD treatment were identified. Most of them were flavonoids, terpenoids, alkaloids, and steroids. The prevalent phytochemical compounds related to treat MSD were 9-hydroxycalabaxanthone, dihydrovaltrate, morroniside, isoacteoside, lithocholic acid, pomiferin, cucurbitacin E, leonuriside A, liriodendrin, and physalin E. Sambucus javanica Reinw. ex Blume (Adoxaceae), Betula alnoides Buch.-Ham. ex D.Don (Betulaceae), Blumea balsamifera (L.) DC. (Asteraceae), Plantago major L. (Plantaginaceae) and Flacourtia jangomas (Lour.) Raeusch. (Salicaceae) all had high ethnobotanical index values and many active compounds.

DISCUSSION AND CONCLUSIONS

This study provides valuable information, demonstrating low-cost medicine plants that are locally available. It is a choice of treatment for people living in remote areas.

Exploration of plant metabolomics variation and absorption characteristics of water-extracted Rheum tanguticum and ethanol-extracted Rheum tanguticum by UHPLC-Q-TOF-MS/MS

BACKGROUND AND OBJECTIVE

The herb Rheum tanguticum (RT), a member of the Polygonaceae family, is listed in the Chinese Pharmacopoeia and has been widely used to treat cardiovascular and gastrointestinal disease. The research aimed to identify the different substances from two kinds of RT extraction methods and the in vivo biotransformation of RT components.

METHODS

In this study, by using ultrahigh-performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS), we have investigated the metabolomic variation and the in vivo metabolism of RT. A post-acquisition data processing software, PeakView, was applied to an accurate qualitative analysis of the chemical components in RT.

RESULTS

Through plant metabolomics analysis, 24 related, differentially expressed metabolites of RT water extract and alcohol extract were obtained. Combined with novel identification strategies and systematic in vivo metabolism analysis, a total of 101 compounds were discovered or tentatively identified in rat serum (including 15 prototype compounds and 86 metabolites).

CONCLUSION

In this study, a combination of extraction methods, liquid chromatography-mass spectrometry (LC-MS) technology, and in vivo animal metabolism studies have been established for the screening, identification, and research of chemical active components of natural medicines. LC-MS analysis combined with plant metabolomics was used to study the differential metabolites between different extraction methods of RT. Based on UHPLC-Q-TOF-MS/MS technology, the composition and metabolism of rat plasma before and after RT administration were analysed in vivo, and 15 prototype components and 86 metabolites were detected.

Quality assessment of Rheum species cultivated in Japan by focusing on M2 polarization of microglia

In traditional Japanese medicine, Rhei Rhizoma is used as a purgative, blood stasis-resolving and antipsychotic drug. The latter two properties are possibly related to anti-inflammatory effects. Microglia regulate inflammation in the central nervous system. M1 microglia induce inflammation, while M2 microglia inhibit inflammation and show neurotrophic effects. This study investigated the effects from water extracts of roots of cultivated Rheum species in Nagano Prefecture, Japan (strain C, a related strain to a Japanese cultivar, 'Shinshu-Daio'; and strain 29, a Chinese strain) and 3 kinds of Rhei Rhizoma available in the Japanese market, and also examined their constituents on the polarization of cultured microglia. All extracts significantly decreased M1 microglia, and strains C and 29 significantly increased M2 microglia. Furthermore, the extracts of both strains significantly increased the M2/M1 ratio. Among the constituents of Rhei Rhizoma, ( +)-catechin (2), resveratrol 4'-O-β-D-(6″-O-galloyl) glucopyranoside (5), isolindleyin (8), and physcion (15) significantly increased the M2/M1 ratio. The contents of the constituents in water extract of each strain were quantified using HPLC. The extracts of strains C and 29 contained relatively large amounts of 2 and 5; and 2, 8, and 15, respectively. This study showed the water extracts of roots of cultivated Rheum strains in Japan had the effects of M2 polarization of microglia, suggesting that these strains become the candidate to develop anti-inflammatory Rhei Rhizoma. Moreover, the suitable chemical composition to possess anti-inflammatory activity in the brain was clarified for the future development of new type of Rhei Rhizoma.

Preparation of magnetic metal-organic framework MIL-101(Fe) and its application in the extraction of anthraquinones in rhubarb

In this work, a magnetic octahedral metal organic framework (Fe₃ O₄ @NH₂ -MIL-101(Fe)) was synthesized for the magnetic solid phase extraction of three anthraquinones, including aloe-emodin, emodin, and physcion, in rhubarb. The Fe₃ O₄ @NH₂ -MIL-101(Fe) exhibited a high specific surface area of 259.2 m² /g with an average pore size of 6.0 nm and a high magnetic responsivity of 23.4 emu/g, which may be used as an adsorbent for rapid preconcentration and separation of target analytes. The main parameters for magnetic solid phase extraction of anthraquinones, including the amount of adsorbent, extraction time, extraction temperature, extraction pH, elution solvent, and elution time, were systematically optimized. The whole extraction process required a very low amount of adsorbent and a small volume of the sample. Besides, under the optimized conditions, the method showed satisfactory spiked recovery for anthraquinones in the range of 93.3%-109.1%, and the LODs were 1.7-3.4 ng/mL. The RSDs for intra- and inter- day precision were 0.2%-1.3% and 0.2%-0.6%, respectively. The experimental results indicate that the developed method is feasible for the analysis of anthraquinones in rhubarb. This article is protected by copyright. All rights reserved.

A comparative study of aurantio-obtusin metabolism in normal and liver-injured rats by ultra performance liquid chromatography quadrupole time-of-flight mass spectrometry

Aurantio-obtusin, an anthraquinone isolated from cassiae semen, possesses diverse pharmacological activities, including hypotensive, hypolipidemic and anti-inflammatory effects. However, our previous studies demonstrated that exposure to aurantio-obtusin induced hepatotoxicity, but the mechanisms of the toxic effects remain unknown. The purpose of the present study is to establish a strategy for the metabolite profiling of aurantio-obtusin in normal and liver-injured rats. This study aimed at identifying the in vivo metabolites and the metabolic profiling in rats after oral administration at a dose of aurantio-obtusin (4 and 200 mg/kg) by using an ultra performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) and metabolynx™ software. A total of 39 metabolites were detected and 3 of them were compared with standard substances. The results indicated that the principal metabolism pathways of aurantio-obtusin in normal rats were glucuronidation and sulfation, while in rats with liver injury, demethylation, dehydroxylation and reduction were also observed and regarded as new metabolic patterns of aurantio-obtusin. These findings helped us to understand the pharmacological and toxicological mechanisms of aurantio-obtusin. Moreover, this study could help to elucidate the metabolic profiling of other anthraquinones.

A machine learning-driven study indicates emodin improves cardiac hypertrophy by modulation of mitochondrial SIRT3 signaling

Cardiac hypertrophy (CH) is an enormous risk factor in the process of heart failure development, however, there is still lack of effective treatment for CH. Mitochondrial protection is an effective way against CH. Rheum palmatum L. (rhubarb) has been used to treat chronic heart diseases such as heart failure, especially to inhibit cardiac compensatory enlargement. The aim of this study was to explore the pharmacodynamic component of rhubarb and reveal its pharmacological effects and targets in the treatment of CH. Based on network pharmacology and machine learning approach, ingredients of rhubarb and targets for CH were extracted and surflex docking was conducted for obtaining the optimal ingredient-target combination(s) and emodin-SIRT3 was identified for further functional analysis. Transverse aortic constriction or isoproterenol induced CH mice and phenylephrine injured cardiomyocytes were used to verify the mitochondria protection effect and CH improvement of emodin in vivo and in vitro by modulation of mitochondrial SIRT3 signaling. The results showed that emodin could block agonist-induced and pressure overload-mediated CH. Emodin prevented mitochondrial dysfunction and its underlying mechanism was attributed to the activation of SIRT3, but the effect was not obvious with the presence of SIRT3 inhibitors (3-TYP)/SIRT3 siRNA. Furthermore, PGC-1ɑ was involved in the process of emodin regulating SIRT3 signaling pathway as an upstream target. Our findings clarified the main material basis and mechanism of rhubarb in the treatment of CH. Emodin, as the major ingredient of rhubarb, has therapeutic potential for CH through mitochondrial protection due to the modulation of SIRT3 signaling.

Antioxidant and Compositional HPLC Analysis of Three Common Bamboo Leaves

Bamboo leaves of Phyllostachys nigra (PN), Lophatherum gracile (LG), and Pleioblastus amarus (PA) are three common herbs in China. In this work, a new high performance liquid chromatography (HPLC) method for the simultaneous determination of seven compounds in bamboo leaves has been developed; and PN, LG, and PA leaves were analyzed. PN showed four times as much chlorogenic acid (CA) than the other two, and contained the most isoorientin (iso-ORI) and isovitexin (iso-VIT) as well. The PA presented the most orientin (ORI) and LG covered a majority of cynaroside (CYN). We measured the antioxidant activity by scavenging the stable 2,2-diphenyl-1-pyridinohydrazinyl (DPPH) free radicals, and found that Luteolin (inhibitory concentration (IC)₅₀ = 0.42 µM, LUT) and CYN (IC₅₀ = 0.43 µM) showed 2–3 times higher antioxidant activity than iso-ORI (IC₅₀ = 0.81 µM), ORI (IC₅₀ = 0.84 µM), and other related antioxidant standards such as trolox (IC₅₀ = 0.97 µM) and ascorbic acid (IC₅₀ = 0.93 µM, VC). Among extracts, PN and PA showed considerable antioxidant activity, which was related well with the contents of CA, iso-ORI, and iso-VIT (p < 0.05). This study firstly provides evidence for functional antioxidant compounds of bamboo leaves based on statistical analysis of the HPLC analysis and DPPH assay, and it lays a foundation for its further development or utilization.

Rheinic acid ameliorates radiation-induced acute enteritis in rats through PPAR-γ/NF-κB

BACKGROUND

Acute radiation enteritis (ARE), a common complication of intestinal caused by abdominal and pelvic radiation therapy. Rheinic acid is a major active ingredient derived from Rhubarb. Rhubarb could suppress inflammation, tumor, fibrosis oxidative damage. However, RA as the main active component and extract monomer of Rhubarb, the pharmacological activity and the underlying molecular mechanism on various diseases has not yet been revealed.

OBJECTIVE

To determine the potential role of rheinic acid (RA) in ameliorating inflammation of rats with acute radiation enteritis (ARE), and explore the underlying mechanism.

METHODS

ARE rat model was established by irradiated with single-dose 10 Gy X-rays at a rate of 0.62 Gy/min to the abdomen. The rats were executed after orally administered with Rheinic acid 7 days and used in the subsequent experiments. Body weight, fecal characteristics and bloody of rats were used to assess the disease activity index. Histological analysis of the jejunum and colon were evaluated using H&E staining. The pro-inflammatory cytokines levels were measured by immunohistochemistry and ELISA. The levels of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) were also determined. The mRNA and protein expression were examined by real-time polymerase chain reaction (qRT-PCR) and western blot, respectively.

RESULTS

Rheinic acid promoted intestinal functional recovery, and ameliorated intestinal damage and bloody stool in ARE rats. Rheinic acid strongly decreased the levels of tumor necrosis factor-α, interleukin-1, interleukin-6, NO, and MDA, whereas increased levels of anti-oxidants, SOD and GSH. Moreover, the expression of apoptosis-related proteins, cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP), were decreased with RA treatment. Further study indicated that PPAR-γ was activated and thereby NF-κB and p38 MAPK signaling pathway were suppressed after rheinic acid treatment.

CONCLUSION

Rheinic acid could ameliorate acute radiation enteritis and the underlying molecular mechanism is, at least partially, through PPAR-γ/NF-κB and p38 MAPK/JNK pathways.

Ameliorative Effect and Mechanism of the Purified Anthraquinone-Glycoside Preparation from Rheum Palmatum L. on Type 2 Diabetes Mellitus

Rheum palmatum L. is a traditional Chinese medicine with various pharmacological properties, including anti-inflammatory, antibacterial, and detoxification effects. In this study, the mechanism of the hypoglycemic effect of purified anthraquinone-Glycoside from Rheum palmatum L. (PAGR) in streptozotocin (STZ) and high-fat diet induced type 2 diabetes mellitus (T2DM) in rats was investigated. The rats were randomly divided into normal (NC), T2DM, metformin (Met), low, middle (Mid), and high (Hig) does of PAGR groups. After six weeks of continuous administration of PAGR, the serum indices and tissue protein expression were determined, and the pathological changes in liver, kidney, and pancreas tissues were observed. The results showed that compared with the type 2 diabetes mellitus group, the fasting blood glucose (FBG), total cholesterol (TC), and triglyceride (TG) levels in the serum of rats in the PAGR treatment groups were significantly decreased, while superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) levels were noticeably increased. The expression of Fas ligand (FasL), cytochrome C (Cyt-c), and caspase-3 in pancreatic tissue was obviously decreased, and the pathological damage to the liver, kidney, and pancreas was improved. These indicate that PAGR can reduce oxidative stress in rats with diabetes mellitus by improving blood lipid metabolism and enhancing their antioxidant capacity, thereby regulating the mitochondrial apoptotic pathway to inhibitβ-cell apoptosis and improve β-cell function. Furthermore, it can regulate Fas/FasL-mediated apoptosis signaling pathway to inhibit β-cell apoptosis, thereby lowering blood glucose levels and improving T2DM.

Antibacterial and antioxidative properties of different parts of garden rhubarb, blackcurrant, chokeberry and blue honeysuckle

BACKGROUND

It is important to find plant materials that can inhibit the growth of Listeria monocytogenes and other food-spoiling bacteria both in vitro and in situ. The aim of the study was to compare antibacterial and antioxidative activity of selected plant-ethanol infusions: leaves and berries of blackcurrant (Ribes nigrum L.), berries of chokeberry (Aronia melanocarpa (Michx.) Elliott) and blue honeysuckle (Lonicera caerulea L. var. edulis); petioles and dark and light roots of garden rhubarb (Rheum rhaponticum L.) for potential use in food matrices as antibacterial and antioxidative additives.

RESULTS

The strongest bacterial growth inhibition was observed in 96% ethanol infusions of the dark roots of rhubarbs. In 96% ethanol, nine out of ten studied plant infusions had antibacterial effect against L. monocytogenes, but in 20% ethanol only the infusions of dark rhubarb roots had a similar effect. Chokeberry and other berries had the highest antioxidative activity, both in 20% and 96% ethanol infusions.

CONCLUSION

The combination of dark rhubarb roots or petioles and berries of black chokeberry, blackcurrant or some other anthocyanin-rich berries would have potential as both antibacterial and antioxidative additives in food. © 2018 Society of Chemical Industry.

Aloe polysaccharide protects skin cells from UVB irradiation through Keap1/Nrf2/ARE signal pathway

The aim of this study was to investigate if aloe polysaccharide (AP) has the repairing effect on ultraviolet b (UVB) injured nerve cells. The study applied BALB/c female mice as animal model, and NFG-activated PC12 cells as cell model of skin nerve. The cell viability was detected by MTT assay, and cell apoptosis was detected by TUNEL (TdT-mediated dUTP nick-end labeling) and Annexin-V/PI assay, and cell-cycle status in different groups were observed via flow cytometry (FCM). Enzyme-linked immunosorbent assay (ELISA) was applied to analyze oxidative stress and anti-oxidative ability in each group. Real-time PCR and western blot were used to detect the expression levels of Bax, Bcl-2, Caspase-3, Cyclin D1, Keap1, Nrf2, GCLC, and GSTP1. The results showed obvious inhibition of cell viability and cell-cycle progression and promotion of cell apoptosis by UVB irradiation through inducing oxidative stress. In AP treated groups, cell viability and proliferation could be markedly improved and cell apoptosis inhibited with higher anti-oxidative capability and up-regulated expression of Keap1, Nrf2, GCLC, and GSTP1. It suggested that AP was able to repair UVB induced injury on NGF activated skin neural cell PC12, probably through Keap1/Nrf2/ARE signal pathway.

Immune defense of emodin enriched diet in Clarias batrachus against Aeromonas hydrophila

This study investigates the effect of emodin enriched diet on growth, hematology, and immune response in walking catfish, Clarias batrachus against Aeromonas hydrophila. The basal (control) diet supplemented with emodin at 0.0, 0.1, 0.2, or 0.4 g kg^-1 was fed to the experimental groups for a period of four weeks. Feeding infected fish with 0.2 g kg^-1 and 0.4 g kg^-1 emodin enriched diets resulted in an overall weight gain, enhanced PER and FCR when compared to other diets. The survival rates were 98.3% and 96.7% in 0.1 g kg^-1 and 0.4 g kg^-1 emodin diet fed groups. Feeding with 0.2 g kg^-1 diet the RBC level significantly elevated on week 1 and with 0.4 g kg^-1 diet on weeks 2 and 4. The WBC, the percentage of globulin and neutrophils increased significantly with 0.2 g kg^-1 diet only on week 4; however with 0.4 g kg^-1 diet the increase was observed from week 1-4. The phagocytic activity increased significantly on being fed with 0.4 g kg^-1 diet on week 2 while with 0.2 g kg^-1 and 0.4 g kg^-1 diets the increase manifested only on week 4; the respiratory burst activity also significantly increased on week 4 whereas increased the complement activity on weeks 2 and 4. The superoxide dismutase (SOD) activity was high on being fed with 0.4 g kg^-1 diet on week 1; with 0.2 g kg^-1 or 0.4 g kg^-1 diets the increase was observed on weeks 2 and 4. The serum IgM level significantly increased when fed with 0.4 g kg^-1 diet whereas the lysozyme activity was enhanced with 0.2 g kg^-1 and 0.4 g kg^-1 emodin diets on weeks 2 and 4. The percentage cumulative mortality was 10% with 0.1 g kg^-1 or 0.2 g kg^-1 diets while with 0.2 g kg^-1 diet it was 15%. The results demonstrate that as a feed additive emodin acts as an immunostimulant enhancing the specific and nonspecific immune defense affording increased disease protection, enhances better growth and boosts hematology parameters in C. batrachus against A. hydrophila infection.

SPE-UHPLC-FLD Method for the Simultaneous Determination of Five Anthraquinones in Human Urine Using Mixed-Mode Bis(tetraoxacalix[2]arene[2]triazine) Modified Silica as Sorbent

The five anthraquinones compounds (including aloe-emodin, emodin, physcion, chrysophanol, and rhein) are regarded as the main effective ingredients in rhubarb (Dahuang in Chinese, one of the commonly used Chinese herbal medicines). In this work, a simple and effective solid phase extraction (SPE) method based on bis(tetraoxacalix[2]arene[2]triazine) modified silica gel as adsorbent was developed. Coupled with UHPLC-FLD, the developed method was successfully applied for the measuring of main anthraquinones in human urine after oral administration of the extracts of rhubarb. To obtain the highest recoveries of the five anthraquinones in the SPE process, the main parameters which may affect extraction efficiency were optimized. The optimized sorbent amount, sample loading pH, sample loading rate, washing solution, and eluent condition were obtained. The developed method showed good linearity in 0.012-1.800 μg mL-1 for the five anthraquinones with correlation coefficients more than 0.9993. The investigated LOD values ranged from 3.9 to 5.7 ng mL-1, while the LOQs were between 12.0 and 18.2 ng mL-1. The recoveries of the method were also investigated, which were in the range of 94.8-106.6%. The application of the mixed-mode SPE materials in the proposed method was feasible and simple, and suitable for the enrichment of anthraquinones in urine samples.

Safety of Daiobotampito in the Treatment of Acute Diverticulitis of the Colon: A Single-Center, Open-Label, Prospective Trial

PURPOSE

The purpose of this study was to investigate the safety of daiobotampito in the treatment of acute diverticulitis of the colon.

METHODS

We conducted a single-center, open-label, prospective study. Ten patients who suffered from diverticulitis of the colon were recruited. The patients were treated with fasting, antibacterial agents, and daiobotampito extract for 10 days in or out of hospital. The patients individually recorded their body temperature, grade of abdominal pain, number of times that analgesics were used, and number of stools daily. We checked whether the patients had adverse reactions such as abdominal pain or diarrhea.

RESULTS

No patients experienced serious adverse reactions. One patient had moderate abdominal pain and diarrhea soon after daiobotampito intake. This patient discontinued daiobotampito on day 4, and the pain and diarrhea quickly resolved. The abdominal pain of this patient was worse 6 days before treatment, and the pain was almost relieved with initial daiobotampito treatment.

CONCLUSIONS

Daiobotampito is a safe treatment option for early stage, acute diverticulitis.

Evaluation of Methanol Induced Free Radicals in Mice Liver

Methanol induced oxidative stress (OS) models in mice were successfully established and evaluated by the electron paramagnetic resonance (EPR) spin trapping technique. The capacity for removal of reactive oxygen species (ROS) free radicals by rhubarb and vitamin C (Vc) as candidate materials was also investigated. EPR was employed to determine the free radicals generated from a spin trapping agent, α-phenyl-N-tert-butylnitrone (PBN), that reacted with the ROS. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX), and the level of malondialdehyde (MDA) were also evaluated by enzyme assays. The results indicated that methanol clearly promoted the generation of ROS free radicals in the liver of mice. The activity of SOD and GSH-PX was reduced significantly, although the level of MDA was increased as a result of the harmful effect of methanol. In addition, rhubarb and Vc exhibited a protective effect on the mice liver under acute OS.

Emodin ameliorates hepatic steatosis through endoplasmic reticulum-stress sterol regulatory element-binding protein 1c pathway in liquid fructose-feeding rats

AIM

To investigate the effects of emodin on the treatment of non-alcoholic fatty liver in rats induced by liquid fructose-feeding in rats and the possible underlying mechanisms.

METHODS

Sprague-Dawley rats were divided into the control, fructose-feeding group, and three fructose-feeding groups treated with 40, 80 and 160 mg/kg emodin, respectively. After 4 weeks of feeding, liquid consumption, food intake, bodyweight, liver index, serum triglyceride (TG), glucose and aminotransferases (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]), liver TG contents and histology features were examined. The hepatic expression of lipogenic and fatty acid oxidation key enzymes, and an upstream transcriptional factor, sterol regulatory element-binding protein 1c (SREBP1c) were determined. Glucose regulated protein 78 (GRP78), a liver endoplasmic reticulum stress (ERS) marker and the unfolded protein response (UPR) related proteins were also measured.

RESULTS

Emodin reduced bodyweight, liver index, serum TG levels of fructose-feeding rats with no significant difference in serum glucose, AST and ALT levels. Emodin improved hepatic steatosis by inhibiting SREBP1c activation and its target genes, and enhancing carnitine palmitoyltransferase 1 expression in fructose-feeding rats. Emodin resolved hepatic ERS and the UPR induced by liquid fructose in rats.

CONCLUSION

Emodin is capable of improving the lipid accumulation through the ERS-SREBP1c pathway in fructose-induced non-alcoholic fatty liver disease.

In vitro antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone induced apoptosis against COLO320 cells through cytochrome c release caspase mediated pathway with PI3K/AKT and COX-2 inhibition

The present study investigated the anticancer activity of 2,3-dihydroxy-9,10-anthraquinone against different cancer cells such as MCF-7, COLO320, HepG-2, Skov-3, MOLM-14, NB-4, CEM, K562, Jurkat, HL-60, U937, IM-9 and Vero. 2,3-dihydroxy-9,10-anthraquinone showed good antiproliferative activity against COLO320 cells when compared to other tested cells. The cytotoxicity results showed 79.8% activity at the dose of 2.07 μM with IC50 value of 0.13 μM at 24 h in COLO320 cells. So we chose COLO320 cells for further anticancer studies. mRNA expression was confirmed by qPCR analysis using SYBR green method. Treatment with 2,3-dihydroxy-9,10-anthraquinone was found to trigger intrinsic apoptotic pathway as indicated by down regulation of Bcl-2, Bcl-xl; up regulation of Bim, Bax, Bad; release of cytochrome c and pro-caspases cleaving to caspases. Furthermore, 2,3-dihydroxy-9,10-anthraquinone stopped at G0/G1 phase with modulation in protein levels of cyclins. On the other hand PI3K/AKT signaling plays an important role in cell metabolism. We found that 2,3-dihydroxy-9,10-anthraquinone inhibits PI3K/AKT activity after treatment. Also, COX-2 enzyme plays a major role in colorectal cancer. Our results showed that the treatment significantly reduced COX-2 enzyme in COLO320 cells. These results indicated antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone involving apoptotic pathways, mitochondrial functions, cell cycle checkpoint and controlling the over expression genes during the colorectal cancer. Molecular docking studies showed that the compound bound stably to the active sites of Bcl-2, COX-2, PI3K and AKT. This is the first report of anticancer mechanism involving 2,3-dihydroxy-9,10-anthraquinone in COLO320 cells. The present results might provide helpful suggestions for the design of antitumor drugs toward colorectal cancer treatment.

Novel 1,5,7-trihydroxy-3-hydroxy methyl anthraquinone isolated from terrestrial Streptomyces sp. (eri-26) with antimicrobial and molecular docking studies

Streptomyces sp. isolate ERI-26 was obtained from the Nilgiris forest soil of Western Ghats, Tamil Nadu, India. Novel anthraquinone compound was isolated from the active fraction 5; it was identified by spectroscopical data using UV, IR, NMR and MASS. The isolated compound 1,5,7-trihydroxy-3-hydroxy methyl anthraquinone was tested against bacteria and fungi at minimum inhibitory concentration level. The compound showed significant antimicrobial activity against bacteria, Staphylococcus aureus at 125 μg/ml, Staphylococcus epidermidis at 62.5 μg/m, Bacillus subtilis at 31.25 μg/ml, fungi; Epidermophyton floccosum at 62.5 μg/ml, Aspergillus niger at 31.25 μg/ml, Aspergiller flavus at 31.25 μg/ml, Trichophyton rubrum at 62.5 μg/ml and Botrytis cinerea at 62.5 μg/ml. The isolated compound was subjected to molecular docking studies for the inhibition of TtgR, topoisomerase IV and AmpC β-lactamase enzymes which are targets for antimicrobials. Docking studies of the compound showed low docking energy indicating its usefulness as antimicrobial agent. 1,5,7-Trihydroxy-3-hydroxy methyl anthraquinone is new, and its antimicrobial and molecular docking properties are reported for the first time.

Antimicrobial and cytotoxicity properties of 2,3-dihydroxy-9,10-anthraquinone isolated from Streptomyces galbus (ERINLG-127)

Streptomyces galbus ERINLG-127 was isolated from the soil samples of the Marapalam forest, Nilgiris, India. The ethyl acetate extract was subjected to activity-guided fractionation by column chromatography over silica gel. This led to the isolation of 2,3-dihydroxy-9,10-anthraquinone as the active principle. The compound showed good antimicrobial activity against tested bacteria and fungi. The minimum inhibitory concentration values of isolated compound were 12.5 μg/mL against Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhimurium, K. pneumoniae (ESBL-3971), K. pneumoniae (ESBL-3894) and Staphylococcus aureus (MRSA). The compound showed prominent cytotoxic activity in vitro against A549 lung adenocarcinoma cancer cell line. It showed 75.1 % activity at the dose of 100 μg/mL with IC50 value of 60 μg/mL. The isolated compound was subjected to molecular docking studies for the inhibition of TtgR and Topoisomerase IV enzymes which are targets for antimicrobials. Docking studies of the compound showed low docking energy indicating its usefulness as antimicrobial agent.

Profiling of phenolic constituents in Polygonum multiflorum Thunb. by combination of ultra-high-pressure liquid chromatography with linear ion trap-Orbitrap mass spectrometry

A simple and effective method was developed for characterization of phenolic constituents in the roots of Polygonum multiflorum by combination of ultra-high-pressure liquid chromatography with linear ion trap-Orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap). Stilbenes, anthraquinones, tannins and naphthalenes were differentiated by diagnostic fragment ions with accurate mass measurements and characteristic fragmentation pathways. Based on the proposed strategy, fifty-nine constituents were characterized or tentatively identified, of which twenty-two constituents were the first to be reported in P. multiflorum and twelve compounds were characterized as potential new compounds. The identification and structure elucidation of these chemicals provided essential data for further phytochemical studies and quality control of P. multiflorum. The results also demonstrated that our novel method can be extended to screen and characterize other phenolic constituents and their metabolites in botanical extracts.

Emodin, a Naturally Occurring Anthraquinone Derivative, Ameliorates Dyslipidemia by Activating AMP-Activated Protein Kinase in High-Fat-Diet-Fed Rats

The aim of this study was to investigate the antiobesity and antihyperlipidaemic effects of emodin on high-fat diet (HFD)-induced obese rats, and on the regulation of the expression of the genes involved in lipid metabolism to elucidate the mechanisms. After being fed HFD for two weeks, Wistar rats were dosed orally with emodin (40 and 80 mg kg(-1)) or pioglitazone (20 mg kg(-1)), once daily for eight weeks. Emodin (80 mg kg(-1) per day) displayed similar characteristics to pioglitazone (20 mg kg(-1) per day) in reducing body weight gain, plasma lipid levels as well as coronary artery risk index and atherogenic index of HFD-fed rats. Emodin also caused dose related reductions in the hepatic triglyceride and cholesterol contents and lowered hepatic lipid droplets accumulation in HFD-fed rats. Emodin and pioglitazone enhanced the phosphorylation of AMP-activated protein kinase (AMPK) and its primary downstream targeting enzyme, acetyl-CoA carboxylase, up-regulated gene expression of carnitine palmitoyl transferase 1, and down-regulated sterol regulatory element binding protein 1 and fatty acid synthase protein levels in hepatocytes of HFD-fed rats. Our findings suggest emodin could attenuate lipid accumulation by decreasing lipogenesis and increasing mitochondrial fatty acid β-oxidation mediated by activation of the AMPK signaling pathway.

Development and application of high-performance liquid chromatography for the study of two new oxyprenylated anthraquinones produced by Rhamnus species

Rhamnus spp. is known to contain biologically active anthraquinone secondary metabolites but the presence of oxyprenylated ones is not reported. To this aim, a new simple, and accurate analytical method was developed to reveal chemical fingerprint of these analytes in plant extracts. Plant samples were analysed after extraction with n-hexane (first step) and methanol (second step) using a C(18) column with a mobile phase composed of 35% of water:65% of methanol (both with 1% formic acid, v/v) at 0.7 mL min⁻¹ flow rate in gradient elution mode. For quantitative analyses, selective detection was performed at 435 nm. The limit of quantification (LOQ) was 0.5 μM, with the only exception of 3-geranyloxyemodin for which the LOQ value was 5.0 μM, and external matrix-matched standard curves showed linearity up to 125 μM. The within- and between-batch precision (RSD%) values ranged from 0.2% to 12.9% while within- and between-batch trueness (bias%) values ranged from 12.2% to 12.7%. The method was applied to evaluate for the first time the presence and the quantities of oxyprenylated anthraquinones in Rhamnus spp. barks as well as the anthraquinone profile of Rhamnus pumila Turra. The proposed method could be directly applied to the selective quantification of these analytes in natural sources.

Hepatotoxicity or hepatoprotection? Pattern recognition for the paradoxical effect of the Chinese herb Rheum palmatum L. in treating rat liver injury

The hepatotoxicity of some Chinese herbs has been a cause for concern in recent years. However, some herbs, such as rhubarb, have been documented as having both therapeutic and toxic effects on the liver, leading to the complex problem of distinguishing the benefits from the risks of using this herb. To comparatively analyze the dose-response relationship between rhubarb and hepatic health, we administrated total rhubarb extract(RE) to normal and carbon tetrachloride(CCl₄)-treated rats for 12 weeks at 4 dosage levels(2.00, 5.40, 14.69 and 40.00 g·kg⁻¹, measured as the quantity of crude material), followed by biochemical and histopathological tests of the rats' livers. A composite pattern was extracted by factor analysis, using all the biochemical indices as variables, into a visual representation of two mathematically obtained factors, which could be interpreted as the fibrosis factor and the cellular injury factor, according to the values of the variable loadings. The curative effect of administering the two lowest dosages of RE to CCl₄-treated rats was mainly expressed as a decrease in the extent of cellular injury. The hepatoprotective mechanism of RE might be related to its antioxidant effect, the antagonism of the free radical damage to hepatocytes caused by CCl₄. By contrast, the RE-induced liver damage was mainly expressed as a significant increase in the amount of fibrosis in both normal rats at all dosage levels and CCl₄-treated rats at the two highest dosage levels. Therefore, the hepatotoxic potential of RE could be attributable to the liver cell fibrosis induced by high doses of the herb. This study illustrates the bidirectional potential of rhubarb and demonstrates the feasibility of using factor analysis to study the dose-response relationships between herbal medicines and hepatotoxicity or the healing effects of these herbs by extracting the underlying interrelationships among a number of functional bio-indices in a holistic manner.

3-Allyl-1-{[3-(4-nitro-phen-yl)-4,5-dihydro-1,3-oxazol-5-yl]meth-yl}-1H-anthra[1,2-d]imidazole-2,6,11(3H)-trione

The mol­ecular structure of the title compound, C₂₈H₂₀N₄O₆, consists of three fused six-membered rings (A,B,C) and one five-membered ring (D). The latter is linked to an isoxazole ring (E) via a methyl­ene unit. A 4-nitro-phenyl substituent (F) is attached to the isoxazole. The fused five and six-membered rings (C,D) are almost coplanar with an r.m.s. deviation of 0.0345 Å and make a dihedral angle of 9.40 (8)° with ring A. The isoxazole and 4-nitro-phenyl rings (E,F) are also almost coplanar with the imidazole and the fused adjacent ring (C,D), forming a dihedral angle of 11.4 (6)°. The crystal packing displays inter­molecular C—H⋯O hydrogen bonding. An intra­molecular C—H⋯O inter­action also occurs.

Simultaneous determination of naphthalene and anthraquinone derivatives in Rumex nepalensis Spreng. roots by HPLC: comparison of different extraction methods and validation

INTRODUCTION

Rumex nepalensis contains mainly anthraquinone and naphthalene derivatives. Although HPLC methods have been reported for the analysis of anthraquinones, neither a phytochemical analysis of Rumex species nor the simultaneous determination of anthraquinone and naphthalene derivatives in other samples has been reported so far.

OBJECTIVE

To develop and validate a HPLC method for the simultaneous determination of anthraquinone and naphthalene derivatives in R. nepalensis roots.

METHODOLOGY

Anthraquinones and naphthalenes were extracted from R. nepalensis roots by three methods (reflux, ultrasonication and pressurized liquid extraction) using methanol. Separation was achieved on an RP C₁₈ column with a gradient mobile phase consisting of 0.05% orthophosphoric acid in water (solvent A) and methanol (solvent B) using a UV detector (254 nm).

RESULTS

Small differences were observed in the contents of anthraquinone and naphthalene derivatives extracted by the three methods. Chrysophanol-8-O-β-D-glucopyranoside and nepodin were detected as major constituents. The method showed a good linearity (r² > 0.9992), high precision (RSD < 5%) and a good recovery (97-105%) of the compounds. The lowest detection limit was found to be 0.97 ng and the method was found to be robust.

CONCLUSION

Reflux and ultrasonication were found to be the best suited methods for the extraction of glycosides and aglycones, respectively. The developed and validated HPLC method is simple, precise and accurate; and can hence be recommended as the method of choice for the analysis of anthraquinones and naphthalenes in R. nepalensis and other Rumex species for both quality control as well as routine analytical purposes.

Quantification of mineral elements of Rheum emodi Wallr. (Polygonaceae)

Present investigation was carried out to estimate mineral elements in Rheum emodi Wallr. by atomic absorption spectroscopy. The samples of R. emodi Wallr., both wild and cultivate populations, were collected from different localities at different altitudes of Uttarakhand, India. The concentration of micro- and macroelements was different in roots and leaves. The concentration of mineral elements was found in both the leaves and roots in the order of K > Ca > Fe > Mn > Na > Zn > Co > Li > Cu.

Comparison of three different extraction methods and HPLC determination of the anthraquinones aloe-emodine, emodine, rheine, chrysophanol and physcione in the bark of Rhamnus alpinus L. (Rhamnaceae)

INTRODUCTION

Rhamnus alpinus L. (Rhamnaceae), a traditional plants in the flora of the Abruzzo region, is known to contain active anthraquinone secondary metabolites. However, the content of anthraquinones varies among R. alpinus samples depending on collection season and site. Thus, using simple, reliable and accurate analytical methods for the determination of anthraquinones in R. alpinus extracts allows comparative study of different methods of extraction.

OBJECTIVE

After a partial validation of an HPLC method for the simultaneous determination of five anthraquinones, aloe-emodine, rheine, emodine, chrysophanol and physcione, in the bark of R. alpinus, we compared three different methods of extraction.

METHODOLOGY

Anthraquinones were extracted from the bark of R. alpinus using different techniques (methanol maceration, ultrasonic and supercritical CO(2) extraction). Separation and quantification of anthraquinones were accomplished using a reversed-phase C(18) column with the mobile phase of H(2)O-methanol (40 : 60, v/v, 1% formic acid) at a wavelength of 254 nm. The qualitative analyses were also achieved at wavelength of 435 nm.

RESULTS

All calibration curves were linear over the concentration range tested (10-200 mM) with the determination coefficients >or=0.991. The detection limits (S/N = 3) were 5 mM for each analytes. All five anthraquinones were found in the samples tested at concentrations reported in experimental data.

CONCLUSION

The described HPLC method and optimised extraction procedure are simple, accurate and selective for separation and quantification of anthraquinones in the bark of R. alpinus and allow evaluation of the best extraction procedure between the tested assays.

Simultaneous determination of five anthraquinones in medicinal plants and pharmaceutical preparations by HPLC with fluorescence detection

A reversed-phase high-performance liquid chromatography (RP-HPLC) method with fluorescence detection for simultaneous determination of five anthraquinones in Rhubarb collected from nine different locations in China, Polygonum cuspidatum, Polygoni multiflori and three pharmaceutical preparations is proposed and validated. Chromatography was carried out at 25 degrees C on a Hypersil C18 column with the isocratic mobile phase of methanol-0.1% aqueous formic acid (85:15, v/v) at a flow rate of 1.0 ml/min. The excitation and emission wavelengths were set at 440 and 540 nm, respectively. A comprehensive validation of the method included tests of sensitivity, linearity, precision and accuracy. The linear regressions were acquired with r>0.999. Satisfactory intra- and inter-day precisions were achieved with R.S.D.s less than 3.95% and the average recovery factors obtained were in the range of 93.2-103.8%.

Antiatherogenic activity of extracts of Argania spinosa L. pericarp: beneficial effects on lipid peroxidation and cholesterol homeostasisThis article is one of a selection of papers published in this special issue (part 1 of 2) on the Safety and Efficacy of Natural Health Products

Prevention of lipoprotein oxidation by natural compounds may prevent atherosclerosis via reducing early atherogenesis. In this study, we investigated for the first time the beneficial properties of methanolic extract of argania pericarp (MEAP) towards atherogenesis by protecting human low-density lipoprotein (LDL) against oxidation while promoting high-density lipoprotein (HDL)-mediated cholesterol efflux. By measuring the formation of malondialdehyde (MDA) and conjugated diene as well as the lag phase and the progression rate of lipid peroxidation, the MEAP was found to possess an inhibitory effect. In addition, MEAP reduced the rate of disappearance of α-tocopherol as well as the apoB electrophoretic mobility in a dose-dependent manner. These effects are related to the free radical scavenging and copper-chelating effects of MEAP. In terms of cell viability, MEAP has shown a cytotoxic effect (0–40 μg/mL). Incubation of3H-cholesterol-loaded J774 macrophages with HDL in the presence of increasing concentrations of MEAP enhanced HDL-mediated cholesterol efflux independently of ABCA1 receptor pathways. Our findings suggest that argania seed pericarp provides a source of natural antioxidants that inhibit LDL oxidation and enhance cholesterol efflux and thus can prevent development of cardiovascular diseases.

Prevention of hepatic oxidative injury by Xiao-Chen-Chi-Tang in mice

The three purgative Cheng-Chi-Tang decoctions (CCTDs) including Ta-Cheng-Chi-Tang (TCCT), Xiao-Chen-Chi-Tang (XCCT), and Tiao-Wei-Chen-Chi-Tang (TWCCT) are used for treating gastrointestinal disorders, including liver diseases in traditional Chinese medicine. However, the underlying mechanisms as liver disease remedies are far from fully clarified. The objective of the study is to investigate and compare the antioxidant activity of the three purgative CCTDs in order to delineate their hepatic protective potential and mechanism. Antioxidant activity measured with the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging test indicated XCCT as the most potent preparation (IC(50) 8.94 microg/ml). In tert-butylhydroperoxide (TBH, 50mM)-induced lipid peroxidation in ICR mice liver homogenates, XCCT also showed stronger and dose-dependent inhibitory activity against TBH-induced malondialdehyde (MDA, a marker of lipid peroxidation) production (IC(50) 53.66 microg/ml). In addition, XCCT showed dose-dependent protective effect against TBH-induced cytotoxicity in normal human Chung liver cells Furthermore, in carbon tetrachloride (CCl(4))-induced acute liver injury model, mice pretreated with 0.2g/kg and 0.4 g/kg of XCCT extracts showed a decrease of 59.8 and 43.1% in serum glutamic oxaloactetic transaminase (GOT) level, 51.4 and 52% in glutamic pyruvate transaminase (GPT) level, along with a reduction of 31 and 15% in MDA level, respectively, similar to the effects exerted by silymarin. XCCT pretreated mice also showed milder necrotic changes in the microscopic picture of the liver. The results suggest that XCCT has significant antioxidant activity and hepatic protection potential.