Identification and bioactivity evaluation of ring-opening and lactone forms of enterolactone from sheep fed flaxseed cake

The previously undescribed lactone ring-opening enterolactone and its sulphate were purified along with the lactone counterparts from the urine of dairy sheep fed flaxseed cake. The structures were determined by NMR and MS analyses. The ring-opening and lactone forms underwent mutual transformation with changes in pH and milk could protect the lactone form. Enterolactone exhibited more effective anti-proliferation activity on MDA-MB-231 breast cancer cells than its ring-opening counterpart, while the ring-opening enterolactone demonstrated more effective anti-osteoporosis activity than the lactone form. The results indicated the potential for targeting biological functions through pH and medium manipulation.

Anti-osteoporosis effects of mammalian lignans and their precursors from flaxseed and safflower seed using zebrafish model

Secoisolariciresinol diglucoside (SDG) and tracheloside (TCL) are the main lignan components of flaxseed cake and safflower seed cake, which are by-products of oil extraction. Both SDG and TCL are metabolized into mammalian lignan enterolactone (EL) with the involvement of intestinal bacteria. In this research, we evaluated the anti-osteoporosis effects of SDG and the in vivo metabolites EL and enterodiol (ED) prepared in our previous work, as well as the newly isolated chemical constituents from safflower seed, including TCL, the lactone ring opening product of TCL (OTCL) and two alkaloids on the alloxan-induced zebrafish model. All the compounds showed significant anti-osteoporosis effects at 80 µM, with p < 0.05 for EL and p < 0.001 for other compounds compared with the model. SDG and TCL showed the most significant and concentration-dependent effects, with p < 0.001 compared with model at 20 µM. The alkaloids, N-coumaroylserotonin glucoside and N-feruloylserotonin glucoside, also showed anti-osteoporosis at 20 µM with p < 0.01, whereas EL, ED, and OTCL showed no significant effects. Quantitative real-time polymerase chain reaction revealed that SDG and TCL upregulated the expression of osteogenic genes Runx2, SP7, OPG, Col1a1a, Alp, ON, OPN, and OCN in alloxan-treated zebrafish. The in vivo metabolite of lignans, EL, showed significant anti-inflammatory effect (p < 0.01) at 20 µM, which might also help to combat osteoporosis and other complications caused by excessive immune response in the body. The results provided scientific data for using the oil extraction by-products as sources of anti-osteoporosis compounds. PRACTICAL APPLICATION: This study found that lignans in flaxseed cake and safflower seed cake exhibited anti-osteoporosis effects by upregulating the expression of osteogenic genes, making the oil extraction by-products sources of anti-osteoporosis compounds.

Chemical Constituents of Cyperus esculentus Leaves and The Protective Effect Against Agricultural Fungicide-Induced Hepatotoxicity

C yperus esculentus is cultivated as a crop plant due to its edible and oily tubers (tiger nut). However, little is known about the phytochemicals and bioeffects of the leaves. This study was conducted to identify and quantify the chemical constituents of C. esculentus leaves and evaluate their bioactivities. By liquid chromatography-mass spectrometry, 30 compounds including flavan-3-ols, caffeic acid derivatives, and flavones, were identified from the leaves. The quantitative analysis revealed that gallocatechin (8), procyanidin B1 (15), catechin (16), chlorogenic acid (19), orientin (30), and luteolin 7-O-glucuronide (31) are the major chemical constituents of C. esculentus leaves. The contents of these six chemical constituents in the leaves collected in September reached to 1460.85 ± 7.66, 10178.77 ± 302.65, 1048.35 ± 17.37, 1722.15 ± 26.13, 5318.62 ± 277.16, and 1526.54 ± 11.95 μg, respectively, in one gram of the dried leaves. The leaf extract (CELE) showed strong antioxidant activity in vitro, with compounds 8, 15, and 19 contributing the most. CELE showed significant protection against the agricultural fungicide tebuconazole-induced developmental toxicity and hepatotoxicity in zebrafish.

Effects and mechanisms of 6-hydroxykaempferol 3,6-di-O-glucoside-7-O-glucuronide from Safflower on endothelial injury in vitro and on thrombosis in vivo

Background: The florets of Carthamus tinctorius L. (Safflower) is an important traditional medicine for promoting blood circulation and removing blood stasis. However, its bioactive compounds and mechanism of action need further clarification.

Objective: This study aims to investigate the effect and possible mechanism of 6-hydroxykaempferol 3,6-di-O-glucoside-7-O-glucuronide (HGG) from Safflower on endothelial injury in vitro, and to verify its anti-thrombotic activity in vivo.

Methods: The endothelial injury on human umbilical vein endothelial cells (HUVECs) was induced by oxygen-glucose deprivation followed by reoxygenation (OGD/R). The effect of HGG on the proliferation of HUVECs under OGD/R was evaluated by MTT, LDH release, Hoechst-33342 staining, and Annexin V-FITC apoptosis assay. RNA-seq, RT-qPCR, Enzyme-linked immunosorbent assay and Western blot experiments were performed to uncover the molecular mechanism. The anti-thrombotic effect of HGG in vivo was evaluated using phenylhydrazine (PHZ)-induced zebrafish thrombosis model.

Results: HGG significantly protected OGD/R induced endothelial injury, and decreased HUVECs apoptosis by regulating expressions of hypoxia inducible factor-1 alpha (HIF-1α) and nuclear factor kappa B (NF-κB) at both transcriptome and protein levels. Moreover, HGG reversed the mRNA expression of pro-inflammatory cytokines including IL-1β, IL-6, and TNF-α, and reduced the release of IL-6 after OGD/R. In addition, HGG exhibited protective effects against PHZ-induced zebrafish thrombosis and improved blood circulation.

Conclusion: HGG regulates the expression of HIF-1α and NF-κB, protects OGD/R induced endothelial dysfunction in vitro and has anti-thrombotic activity in PHZ-induced thrombosis in vivo.

Identification and bioactivity evaluation of flavan-3-ols in the milk of dairy sheep fed Cynomorium songaricum

Cynomorium songaricum is a traditional medicine and also a food material that is eaten raw or processed as tea or beverages. As a featured plant in semi-desert grasslands, C. songaricum is also eaten by the cattle and sheep in the area. This research study fed dairy sheep C. songaricum to determine the flavan-3-ols in sheep milk. Catechin (Cat), epicatechin (Epi), procyanidin A1 (A1), procyanidin A2 (A2), and procyanidin B1 (B1) were detected in sheep milk with the concentration being Epi > A2 > Cat > B1 > A1 at 24 h after the administration of C. songaricum. Neither A1 nor A2 were detected in the methanol extract of C. songaricum. Cysteine degradation of the plant revealed that in addition to Epi, A2 was the extending unit of the polymeric flavan-3-ols in C. songaricum, indicating that A2 is released digestively from the polymers and enters the milk. Procyanidin B-1 was converted to A1 on incubation in raw but not heated milk, indicating that the A1 in milk is the enzymatically transformed product of B1. Accelerated oxidation showed that the flavan-3-ols, B1, Cat, and Epi significantly protects the unsaturated triacyglycerols in the milk from oxidation. The flavan-3-ol could slow down the oxidation of glutathione and the latter may play an important role in preventing the milk triglycerides from oxidation. Flavan-3-ols are polyphenols with many health benefits. The present research revealed the antioxidant activities of flavan-3-ols that could be absorbed to sheep milk, adding new evidences for the values of these flavan-3-ols and for the milk.

Combination of Ephedra sinica stems and Terminalia chebula fruits produces new ephedrine derivatives in vivo that diminish the permeability to BBB while retaining airway dilation and hepatoprotective effects

ETHNOPHARMACOLOGICAL RELEVANCE

The stems of Ephedra sinica and the fruits of Terminalia chebula are combined using in traditional Mongolian medicine formula "Gurigumu-7" for liver diseases. E. sinica stems contains ephedrine with broncho-dilatory activity. However, ephedrine can pass through the blood-brain barrier (BBB) and excite the central nervous system (CNS) to cause insomnia and restlessness.

AIM OF THE STUDY

The present study was to investigate the structures and bioactivities of new compounds formed in vivo after co-administration of E. sinica stems and T. chebula fruits.

MATERIALS AND METHODS

Pharmacokinetic investigation was carried out in rats. A parallel artificial membrane permeability measurement system was used to determine BBB permeability. Ex vivo experiments using tracheal rings of guinea pig was performed to examine the tracheal relaxation effect. In vivo hepatoprotective tests were carried out in Tg (fabp10a: dsRed) liver transgenic zebrafish. The fluorescent probe, 2,7-dichlorodihydrofluorescein diacetate, was used to measure reactive oxygen species, and UHPLC-MS was used to determine glutathione concentrations after derivatization with N-ethylmaleimide.

RESULTS

New ephedrine derivatives (1 and 2) formed in vivo and reached their maximum serum concentrations at 0.5 h after administration of the two herbal drugs. Compounds 1 and 2 showed lower BBB permeability than ephedrine, suggesting that they have less adverse effects on the CNS. Compounds 1 and 2 relaxed the tracheal rings and had strong hepatoprotective effect on transgenic zebrafish with liver specific expression of RFP. Compounds 1 and 2 significantly reduced the level of reactive oxygen species while increasing that of glutathione in thioacetamide-treated zebrafish, which might be the hepatoprotective mechanism.

CONCLUSION

These results provided evidences that the chemical constituents in various herbal drugs in a medicinal formula can interact to generate new compounds with fewer side effects and increased or additive bioactivity.

Hydroxysafflor yellows alleviate thrombosis and acetaminophen-induced toxicity in vivo by enhancing blood circulation and poison excretion

BACKGROUND

Hydroxysafflor yellow A (HSYA) from the flower of Carthamus tinctorius (Safflower) has been reported to have various pharmacological effects. However, little is known about the bioactivities of other chemical constituents in Safflower and the relationship between enhancement of blood circulation and hepatoprotection by HSYA.

PURPOSE

The present research was to evaluate the antithrombotic and hepatoprotective activities of HSYA and C, examine their mechanisms of actions, including influence on the excretion velocity of acetaminophen, and the relationship between the antithrombotic, hepatoprotective, and other bioactivities.

METHODS

The hepatoprotective activities were examined by acetaminophen (APAP)-induced zebrafish toxicity and carbon tetrachloride (CCl4)-induced mouse liver injury. The concentrations of APAP in zebrafish and APAP that was excreted to the culture media were quantified by UHPLC-MS. The anti-thrombosis effect of HSYA and C were examined by the phenylhydrazine (PHZ)-induced zebrafish thrombosis.

RESULTS

HSYA and HSYC showed robust protection on APAP-induced toxicity and PHZ-induced thrombosis. The hepatoprotective effects of HSYA and C were more potent than that of the positive control, acetylcysteine (61.7% and 58.0%, respectively, vs. 56.9% at 100 µM) and their antithrombosis effects were more robust than aspirin (95.1% and 86.2% vs. 52.7% at 100 µM). HSYA and C enhanced blood circulation, rescued APAP-treated zebrafish from morphological abnormalities, and mitigated APAP-induced toxicity in liver development in liver-specific RFP-expressing transgenic zebrafish. HSYC attenuated CCl4-induced mouse liver injury and regulated the levels of HIF-1α, iNOS, TNF-α, α-SMA, and NFκB in liver tissues. HSYA was also protective in a dual thrombotic and liver toxicity zebrafish model. By UHPLC-MS, HSYA accelerated the excretion of APAP.

CONCLUSION

HSYA and C are the bioactive constituents of Safflower that are responsible for the herbal drug's traditional use in promoting blood circulation to remove blood stasis. Safflower and its chalcone constituents may protect from damage due to exogenous or disease-induced endogenous toxins by enhancing the excretion velocity of toxins.

In vivo hepatoprotective activity and the underlying mechanism of chebulinic acid from Terminalia chebula fruit

BACKGROUND

The fruit of Terminalia chebula Retz. is one of the most widely used herbal drug in Traditional medicine prescriptions including those for liver diseases. In the screening of bioactive constituents that have potential hepatoprotective activity, chebulinic acid (CA) which is a major chemical constituent of T. chebula fruit showed potent activity.

PURPOSE

This work was conducted to investigate the hepatoprotective activity and mechanisms of CA.

METHODS

The hepatoprotective effect of CA was examined on hepatotoxic models of cells, zebrafish larvae and mice caused by tert-butyl hydrogen peroxide (t-BHP), acetaminophen (APAP) and CCl4, respectively.

RESULTS

Pretreatment with CA could prevent t-BHP-induced damage in L-02 hepatocytes by blocking the production of ROS, reducing LDH levels and enhancing HO-1 and NQO1 expression via MAPK/Nrf2 signaling pathway. In animal experiments, CA significantly protected mice from CCl4-induced liver injury, as demonstrated by reduced ALT, AST and MDA levels, enhanced SOD activity, improved liver histopathological changes, and the activation of the Nrf2/HO-1 signaling pathway. CA metabolized to chebulic acid isomers with DPPH radical scavenging activity. In a transgenic zebrafish line with liver specific expression of DsRed RFP, CA diminished the hepatotoxicity induced by 10 mM APAP.

CONCLUSION

Experiments in cell and two animal models demonstrated consistent results and comprehensively expounded the hepatoprotective effects of CA.

[ABO gene subtypes and gene expression analysis in three cases of hematological malignancies patients]

Objective: To explore the application and discovery of genotyping, gene sequencing, and gene expression analysis in the determination of ABO blood group subtypes and antigen expression abnormalities in hematological malignancies patients. Methods: From June 2019 to May 2020, three clinical cases were found with forward and reverse ABO typing discrepancy or atypical serologic agglutination pattern in the laboratory and blood transfusion department of Hebei Yanda Ludaopei Hospital were selected. Sequence-specific primer PCR (PCR-SSP) and Sanger sequencing of ABO gene coding regions were performed to determine the ABO genotypes, and whole transcriptome sequencing was used to analyze ABO and FUT1 gene expression levels. Results: A 12-year-old female acute lymphoblastic leukemia patient was determined as O.01.02 and BA.04 sub-genotype, corresponding to the serological B(A) subtype, and her ABO gene expression was normal (354.80). A 41-year-old female acute myeloid leukemia patient was determined as A1.02 and B.01 genotype, corresponding to the serological A(1)B phenotype, and her ABO gene expression was significantly reduced (45.70). A 42-year-old male with myelodysplastic syndrome and myelofibrosis was determined as A1.02 and A2.05 sub-genotype, corresponding to the serological A(1) and A(2) phenotype, respectively, and his ABO expression was negative. FUT1 expression was in the normal range in all three cases. The clinical blood product infusion strategy was formulated according to the genotype and the corresponding immunological subtype, and no significant transfusion-related adverse reactions occurred. Conclusion: Blood group sub-genotypes or aberrant gene expression can lead to ambiguities in serological blood group determination in hematological malignancies patients. ABO genotyping and gene expression analysis can help in this scenario and escort blood product infusion safety.

Technical note: Quantification of lignans in the urine, milk, and plasma of flaxseed cake-fed dairy sheep

Mammalian lignans are phytoestrogens with important bioactivities, and their concentrations in livestock milk may influence the health of consumers. This research aimed to establish a method to quantify multiple mammalian lignans in the biofluids of dairy sheep using ultra-HPLC-triple quadropole mass spectrometry with multiple-reaction monitoring. Secoisolariciresinol, 2-[(4-hydroxy-3-methoxyphenyl)methyl]-3-[(3-hydroxyphenyl)methyl]-1,4-butanediol, enterodiol (ED), enterolactone (EL), ED-sulfate (ED-S), and EL-sulfate (EL-S) were purified from the urine of flaxseed cake-fed dairy sheep. The structures of these lignans were identified by a combination of mass and nuclear magnetic resonance spectra. These purified lignans were used as standards to optimize their quantification conditions in urine, milk, and plasma of dairy sheep. On this basis, the lignan metabolites in biofluids were quantified. To improve analysis sensitivity, plasma and milk were pretreated with acetonitrile containing 1% formic acid and passed through a HybridSPE-PL 55261-U column (Supelco, Bellefonte, PA). The limit of quantification of the lignans ranged from 1.43 to 18.3 ng/mL in plasma, and from 1.01 to 18.7 ng/mL in milk. The linearity of the calibration curves ranged from their limit of quantification to at least 217 ng/mL in plasma, and 217 ng/mL in milk. Regression coefficient of the calibration curves were above 0.99 for secoisolariciresinol, 2-[(4-hydroxy-3-methoxyphenyl)methyl]-3-[(3-hydroxyphenyl)methyl]-1,4-butanediol, ED, EL, ED-S, and EL-S, indicating satisfactory relationships between the peak areas and concentrations in the quantification range. The relative concentrations of ED-glucuronide and EL-glucuronide (EL-G) in different biofluids were compared based on their chromatogram peak areas. The sheep plasma contained all forms of mammalian lignans (i.e., ED, EL, ED-S, EL-S, ED-glucuronide, and EL-G.); the urine contained ED, EL, ED-S, and EL-S; and the milk contained ED, EL, ED-S, EL-S, and EL-G. Milk-to-plasma concentration ratios of the mammalian lignans indicated that the free forms were more permeable than the sulfated conjugates. Mammalian lignans found in sheep plasma and milk may provide health benefits to the sheep and sheep-product consumers. The analytical method established in this work could be used to quantify mammalian lignans in livestock products.

Constituents from the Leaves of Tetraena mongolica and Their Protective Activity in HEK 293t Cells Damaged by CdCl2

Tetraena mongolica Maxim, a relict originating from the Tertiary Period, is an endemic species of Zygophyllaceae in China. Three new monoterpenoids (1-3), two new phenols (4, 5) with unusual O-sulfoglucosyl groups, a new flavonoid (6), and nine known compounds were isolated from the leaves of T. mongolica. The structures of these compounds were determined by interpretation of NMR, MS, and ECD data. Some of the isolated compounds showed protective effects on HEK 293t cells damaged by CdCl₂, with IC₅₀ values being 55.7 and 80.3 μM for compounds 7 and 8, respectively, at the time point of 48 h after treatment.

Inhibitory effects and molecular mechanisms of pentagalloyl glucose in combination with 5-FU on aggressive phenotypes of HepG2 cells

This study examined the inhibition and mechanism of natural product pentagalloyl glucose (PGG) against HepG2 cells and determined the effects of its combination with the clinical chemotherapeutic drug, 5-FU. PGG was found to inhibit the proliferation, migration and invasion of HepG2 cells, induced G1 arrest and apoptosis in both concentration- and time- dependent manners. The combination of PGG and 5-FU had synergistic effects on reversal the aggressive phenotypes of HepG2 cells, increasing the proportion of Bax/Bcl-2, promoting the activation of caspase-9 and caspase-3, and inducing apoptosis. This combination upregulated P27 and cyclin B1, and downregulated cyclin E1, leading to G1 phase arrest. The combination significantly downregulated MDR1 and LRP1, suggesting the potential to reverse the resistance to 5-FU.

Structures and In Vitro Antihepatic Fibrosis Activities of Prenylated Dihydrostilbenes and Flavonoids from Glycyrrhiza uralensis Leaves

Glycyrrhiza uralensis is the major plant source of licorice. This study was to identify bioactive compounds from the plant's leaves in order to make better use of its aerial part. An ethanol extract of the leaves was subjected to repeated chromatography to yield 15 compounds. The structures were determined to be three novel dihydrostilbenes, based on their various spectroscopic data-glycypytilbene A (1), glycydipytilbene (2), and glycypytilbene B (3)-and 12 known compounds, α,α'-dihydro-3,5,4'-trihydroxy-4,3'-diisopentenylstilbene (4), α,α'-dihydro-3,5,3',4'-tetrahydroxy-2,5'-diisopentenylstilbene (5), 6-prenyleriodictyol (6), 5'-prenyleriodictyol (7), 6-prenylquercetin-3-Me ether (8), 5'-prenylquercetin (9), 6-prenylquercetin (10), 6-prenylnaringenin (11), 3'-prenylnaringenin (12), sigmoidin C (13), 8-[(E)-3-hydroxymethyl-2- butenyl]-eriodictyol (14), and quercetin-3-Me ether (15). Most of these chemical constituents inhibited α-glucosidase activity, with the two prenylated quercetin derivatives (9 to 10) being the greatest active (IC₅₀ < 4.0 µg/mL). Compounds 1, 3 to 4, 6 to 7, 9 to 12 impeded the growth of human hepatic stellate cells, with the prenylated flavonoids (6 to 7, 9 to 12) being more robust than their unprenylated counterparts. PRACTICAL APPLICATIONS: This study found that Glycyrrhiza uralensis leaves contain prenylated dihydrostilbenes and flavonoids with inhibiting effects on α-glucosidase and on the proliferation of human hepatic stellate cells, which should prompt the development of G. uralensis leaves for healthy products with anti-diabetic or liver fibrosis-preventing effects.

Comparison of Antioxidant Constituents of Agriophyllum squarrosum Seed with Conventional Crop Seeds

Twelve chemical constituents were identified from the Agriophyllum squarrosum seed (ASS). ASS contained large amounts of flavonoids, which were more concentrated in the seed coat. ASS-coat (1 g) contained 335.7 μg flavonoids of rutin equivalent, which was similar to the flavonoid content in soybean (351.2 μg/g), and greater than that in millet, wheat, rice, peanut, and corn. By LC-MS analysis, the major constituents in ASS were 3-O-[α-L-rhamnopyranosyl-(1→6)-β-D- glucopyranosyl]-7- O-(β-D-glucopyranosyl)-quercetin (1), rutin (4), quercetin-3-O-β-D- apiosyl(1→2)-[α-L-rhamnosyl(l→6)]-β-D-glucoside (2), isorhamnetin-3-O-rutinoside (5), and allantoin (3), compared with isoflavonoids-genistin (16), daidzin (14), and glycitin (18) in soybean. Among constituents in ASS, compounds 1, 2, 4, protocatechuic acid (8), isoquercitrin (11), and luteolin-6-C-glucoside (12) potently scavenged DPPH radicals and intracellular ROS; strongly protected against peroxyl radical-induced DNA scission; and upregulated Nrf2, phosphorylated p38, phosphorylated JNK, and Bcl-2 in HepG2 cells. These results indicate that ASS is rich in antioxidant constituents that can enrich the varieties of food flavonoids, with significant beneficial implications for those who suffer from oxidative stress-related conditions.

PRACTICAL APPLICATION

This study found that A. squarrosum seed contains large amounts of antioxidative flavonoids and compared its chemical constituents with those of conventional foods. These results should increase the interest in planting the sand-fixing A. squarrosum on a large scale, thus preventing desertification and providing valuable foods.

Quantification of Bile Acids in Traditional Animal Medicines and Their Preparations Using Ultra High-Performance Liquid Chromatography-Mass Spectrometry in the Multiple Reaction Monitoring Mode

An ultra-high-performance liquid chromatograph-triple quadrupole mass spectrometry has been established and validated for the simultaneous quantification of 15 bile acids in four traditional animal medicines and their preparations. The separations of bile acids were performed on an Agilent ZORBAX Eclipse XDB-C18 column (50 × 2.1 mm; 1.8 μm) with methanol-0.1% formic acid as the mobile phase. Glycyrrhetinic acid was added as internal standard owing to its similar physiochemical properties with the bile acids. Using this condition, detected in the multiple reaction monitoring mode, the 15 bile acids, including three groups of isomers, were well quantified individually. Method validation showed that the linear regression relationship (r(2), 0.9993 - 0.9999), precisions (intra-day RSD, 0.96 - 4.31%; inter-day, 1.73 - 4.43%), and recovery (95.3 - 120.9%) were all satisfactory. The analysis results showed that bear bile and bezoar (Niu Huang) as well as their formulations contained large amounts of most of the 15 bile acids. In addition, this research revealed for the first time the presences of bile acids in animal waste medication used in traditional medicine from two clinics, Hei-Bing-Pian (discharges of wild boar) and Trogopterus Dung. The established method could be used for the quantification of other bile- or animal waste-based crude drugs and their formulated products.

Lignans, flavonoids and coumarins from Viola philippica and their α-glucosidase and HCV protease inhibitory activities

Two lignans including a new one, five flavonoids and five coumarins were isolated from the whole plant of Viola philippica (synonymised as Viola yedoensis Makino). The new compound was structurally determined as (7R,8S,8'S) -3,3'-dimethoxy- 4,4',9-trihydroxy- 7,9'-epoxy-8,8'-lignan 9-O-rutinoside by analysis of its NMR, MS and CD spectroscopic data. The known compounds were characterised by comparing their NMR and MS data with those reported. Among the known compounds, 5-hydroxy-4'-methoxyflavone-7-O- rutinoside, 6,7-di-O-β-D- glucopyranosylesculetin, and 7R,8S-dihydrodehydrodiconiferyl alcohol 4-O-β-D- glucopyranoside were isolated and identified from this genus for the first time. Of these compounds, 5-hydroxy-4'-methoxyflavone-7-O-rutinoside and (7R,8S,8'S) -3,3'-dimethoxy- 4,4',9-trihydroxy- 7,9'-epoxy-8,8'-lignan 9-O-rutinoside were potently active against α-glucosidase, while the two dimeric coumarins, 5, 5'-bi (6, 7-dihydroxycoumarin) and 6,6',7,7'-tetrahydroxy-5,8'-bicoumarin potently inhibited HCV protease.

Identification and Enrichment of α-Glucosidase-Inhibiting Dihydrostilbene and Flavonoids from Glycyrrhiza uralensis Leaves

To exploit Glycyrrhiza uralensis resources, we examined the bioactive constituents of G. uralensis leaves. Seven chemical components were isolated by repeat column chromatography, and using spectroscopic methods, their structures were determined to be a novel prenylated dihydrostilbene, α,α'-dihydro-3,5,3',4'-tetrahydroxy-2,5'-diprenylstilbene (1); a methylated flavonoid, quercetin-3-Me ether (4); and 5 prenylated flavonoids: 5'-prenylquercetin (3), 8-[(E)-3-hydroxymethyl-2-butenyl]eriodictyol (7), 6-prenyleriodictyol (5), 5'-prenyleriodictyol (6), and 6-prenylquercetin-3-Me ether (2). Compounds 1-7 and their unprenylated counterparts, glycosides, and other related compounds (8-13) were quantitatively analyzed. Using a macroporous resin column, most of these compounds could be enriched in the 40% to 60% ethanol-eluted fractions. Compounds 1-7 showed strong radical scavenging activity toward DPPH, and most of them demonstrated greater inhibitory activity against α-glucosidase than their unprenylated counterparts.

Simultaneous quantification of ten constituents of Xanthoceras sorbifolia Bunge using UHPLC-MS methods and evaluation of their radical scavenging, DNA scission protective, and α-glucosidase inhibitory activities

The present study was designed to investigate the bioactive constituents of Xanthoceras sorbifolia in terms of amounts and their antioxidant, DNA scission protection, and α-glucosidase inhibitory activities. Simultaneous quantification of 10 X. sorbifolia constituents was carried out by a newly established ultra-high performance liquid chromatography-quadrupole mass spectrometry method (UHPLC-MS). The antioxidant activities were evaluated by measuring DPPH radical scavenging and DNA scission protective activities. The α-glucosidase inhibitory activities were investigated by using an assay with α-glucosidase from Bacillus Stearothermophilus and disaccharidases from mouse intestine. We found that the wood of X. sorbifolia was rich in phenolic compounds with the contents of catechin, epicatechin, myricetin, and dihydromyricetin being 0.12-0.19, 1.94-2.16, 0.77-0.91, and 6.76-7.89 mg·g(-1), respectively. The four constituents strongly scavenged DPPH radicals (with EC50 being 4.2, 3.8 and 5.7 μg·mL(-1), respectively) and remarkably protected peroxyl radical-induced DNA strand scission (92.10%, 94.66%, 75.44% and 89.95% of protection, respectively, at a concentration of 10 μmol·L(-1)). A dimeric flavan 3-ol, epigallocatechin-(4β→8, 2β→O-7)-epicatechin potently inhibited α-glucosidase with an IC50 value being as low as 1.2 μg·mL(-1). The established UHPLC-MS method could serve as a quality control tool for X. sorbifolia. In conclusion, the high contents of antioxidant and α-glucosidase inhibitory constituents in X. sorbifolia support its use as complementation of other therapeutic agents for metabolic disorders, such as diabetes and hypertension.

Comparison of pharmacokinetic profiles of Terminalia phenolics after intragastric administration of the aqueous extracts of the fruit of Terminalia chebula and a Mongolian compound medicine-Gurigumu-7

ETHNOPHARMACOLOGICAL RELEVANCE

The dried fruit of Terminalia chebula (fructus chebulae) is an important Traditional Medicine used for intestinal and hepatic detoxification. Gurigumu-7 which is made of fructus chebulae and 6 other traditional medicines is one of the most frequently used compound Mongolian and Tibet medicines for liver diseases. Terminalia phenolics are considered as the bioactive constituents of fructus chebulae and consequently of Gurigumu-7.

AIM OF THE STUDY

To compare the pharmacokinetic profiles of Terminalia phenolics after intragastric administration of the aqueous extracts of fructus chebulae and Gurigumu-7 and to evaluate the possible influence of intestinal bacterial metabolism on these pharmacokinetic profiles.

MATERIALS AND METHODS

An ultra performance liquid chromatography with triple quadrupole mass spectrometry method was established and validated for simultaneously determining the pharmacokinetic profiles of seven Terminalia phenolics after intragastric administration of pure compounds, fructus chebulae extract, and Gurigumu-7 extract. In vitro rat fecal lysates experiments were carried out to explore the metabolic discrepancy between fructus chebulae and Gurigumu-7.

RESULTS

Seven Terminalia phenolics were detected in rat plasma after intragastric administration of the aqueous extracts of fructus chebulae and Gurigumu-7. Administration of Gurigumu-7 could promote the absorption and increase the Cmax and AUC values of these phenolic constituents compared to fructus chebulae administration. The fecal lysates studies showed that the Terminalia phenolics in Gurigumu-7 were less rapidly bio-transformed than those in fructus chebulae. This may be a contributing factor to the pharmacokinetic discrepancy between the phenolics in fructus chebulae and Gurigumu-7.

CONCLUSION

Administration of Gurigumu-7 could increase the absorption of Terminalia phenolics through slowing down the intestinal bacteria metabolism. These results provide, in part, an in vivo rationale for the formulation of the traditional Mongolia / Tibet medicine, Gurigumu-7.

Synthesis of piscidinol A derivatives and their ability to inhibit HIV-1 protease

Four types of piscidinol A derivatives were synthesized and evaluated their ability to inhibit HIV-1 protease to understand their structure-activity relationships. Of these tirucallane-type triterpene derivatives, an A-seco derivative (1b) moderately inhibited human immunodeficiency virus (HIV) protease (IC50 38.2 μM). The 2,2-dimethyl succinic acid (DMS) acylated tirucallane derivatives (4b, 6a, and 7b, 50 < IC50 < 100 μM) were more inhibitory against HIV-1 PR than the others (PA, 2a, 4a, 4c-4d, 5a, 6b-6d, and 7a, IC50 > 100 μM). These findings indicated that the 2,3-seco-2,3-dioic acid (1b) and DMS-acylated tirucallane-type derivatives preferably inhibited HIV viral protease.

Quantification and antioxidant and anti-HCV activities of the constituents from the inflorescences of Scabiosa comosa and S. tschilliensis

To investigate the bioactive constituents of the inflorescences of Scabiosa comosa and S. tschilliensis, which are used traditionally for liver diseases, we tested the antioxidant activity using 2,2'-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), ferric reducing antioxidant potential (FRAP), and DPPH-ultra high performance liquid chromatography-mass spectrometer (UPLC-MS) assay. In addition, cell-based anti-HCV activity of the major compounds were evaluated. The plant extracts showed strong antioxidant activity. For the first time, 3,4-dicaffeoylquinic acid (DCQA), 3,5-DCQA and 4,5-DCQA were identified from genus Scabiosa. A UPLC-MS method in multiple reaction monitoring (MRM) mode was established to quantify 18 constituents in the inflorescences of Scabiosa. The 3,5-DCQA, chlorogenic acid and some glycosides of luteolin or apigenin were found to be the most abundant constituents. Chlorogenic acid and 3,5-DCQA showed excellent radical scavenging activity and demonstrated anti-HCV activity. These findings provided scientific evidences for the clinic use of this herbal medicine for liver diseases.

Chemical constituents of gold-red apple and their α-glucosidase inhibitory activities

Ten compounds were isolated and purified from the peels of gold-red apple (Malus domestica) for the 1st time. The identified compounds are 3β, 20β-dihydroxyursan-28-oic acid (1), 2α-hydroxyoleanolic acid (2), euscaphic acid (3), 3-O-p-coumaroyl tormentic acid (4), ursolic acid (5), 2α-hydroxyursolic acid (6), oleanolic acid (7), betulinic acid (8), linolic acid (9), and α-linolenic acid (10). Their structures were determined by interpreting their nuclear magnetic resonance and mass spectrometry (MS) spectra, and by comparison with literature data. Compound 1 is new, and compound 2 is herein reported for the 1st time for the genus Malus. α-Glucosidase inhibition assay revealed 6 of the triterpenoid isolates as remarkable α-glucosidase inhibitors, with betulinic acid showing the strongest inhibition (IC50 = 15.19 μM). Ultra-performance liquid chromatography-electrospray ionization MS analysis of the fruit peels, pomace, flesh, and juice revealed that the peels and pomace contained high levels of triterpenes, suggesting that wastes from the fruit juice industry could serve as rich sources of bioactive triterpenes.

Baicalein 6-O-β-D-glucopyranuronoside is a main metabolite in the plasma after oral administration of baicalin, a flavone glucuronide of scutellariae radix, to rats

Baicalin (BG) and its aglycone, baicalein (B) are strong antioxidants that exert various pharmacological actions and show unique metabolic fates in the rat. The aim of the present study was to identify major metabolite(s) besides BG in rat plasma after oral administration of BG or B. The main metabolite was detected by HPLC equipped with an electrochemical detector at a potential of +500 mV and identified as baicalein 6-O-β-D-glucopyranuronoside (B6G) by HPLC/MS/MS. When BG at a dose of 20 mg/kg was administered orally to Wistar rats, the level of B6G in plasma was higher than that of BG. Cmax and the area under the concentration-curve from 0 to 24 h (AUC0-24 h) values of the plasma B6G were 1.66 ± 0.34 µM and 19.8 3.9 ± µM · h, respectively, whereas those of BG were 0.853 ± 0.065 µM and 10.0 ± 3.1 µM · h, respectively. When B was administered, similar results were also obtained. B6G-producing activities from B were found in microsomes of both rat jejunum and liver, in spite of the low activity. Rat everted jejunal sacs formed B6G after application of B, but only in a small amount that was excreted into the mucosal side, and not the serosal side, indicating little contribution to the appearance of B6G in plasma. On the other hand, when B was injected into the rat portal vein, B6G was detected at a higher level than BG in the systemic circulation, demonstrating the hepatic contribution to the appearance of plasma B6G.

Chemical constituents and pharmacologic actions of Cynomorium plants

The stem of Cynomorium songaricum is a traditional Chinese medicine reputed to have tonic effects. C. coccineum growing in northern Africa and the Mediterranean region is regarded in Arabian medical practice as the "treasure of drugs". The major constituents of Cynomorium plants have been revealed to be phenolic compounds, steroids, triterpenes, etc. Pharmacologic studies showed that the Cynomorium plants had antioxidant, immunity-improving, anti-diabetic, neuroprotective, and other bioactivities. Some chemical constituents in Cynomorium plants are unstable, implying that the chemical components of the herbal medicines produced under different conditions may be variable. This review covers the literature published until December, 2011 and describes the pharmacologic effects and secondary metabolites of Cynomorium species.

Chemical constituents and pharmacologic actions of Cynomorium plants

The stem of Cynomorium songaricum is a traditional Chinese medicine reputed to have tonic effects. C. coccineum growing in northern Africa and the Mediterranean region is regarded in Arabian medical practice as the "treasure of drugs". The major constituents of Cynomorium plants have been revealed to be phenolic compounds, steroids, triterpenes, etc. Pharmacologic studies showed that the Cynomorium plants had antioxidant, immunity-improving, anti-diabetic, neuroprotective, and other bioactivities. Some chemical constituents in Cynomorium plants are unstable, implying that the chemical components of the herbal medicines produced under different conditions may be variable. This review covers the literature published until December, 2011 and describes the pharmacologic effects and secondary metabolites of Cynomorium species.

Isolation, identification and quantification of unsaturated fatty acids, amides, phenolic compounds and glycoalkaloids from potato peel

Eleven compounds were isolated from potato peels and identified. Their structures were determined by interpretation of UV, MS, 1D, and 2D NMR spectral data and by comparison with reported data. The main components of the potato peels were found to be chlorogenic acid and other phenolic compounds, accompanied by 2 glycoalkaloids, 3 low-molecular-weight amide compounds, and 2 unsaturated fatty acids, including an omega-3 fatty acid. The potato peels showed more potent radical scavenging activity than the flesh. The quantification of the 11 components indicated that the potato peels contained a higher amount of phenolic compounds than the flesh. These results suggest that peel waste from the industry of potato chips and fries may be a source of useful compounds for human health.

Determination of novel nitrogen-containing metabolite after oral administration of swertiamarin to rats

In a series of studies on the metabolism of iridoid compounds, we investigated the metabolic fate of swertiamarin (1) in Wistar rats. Liquid chromatography/ion trap mass spectrometry detected new nitrogen-containing metabolite gentiandiol (3) in rat plasma. The structure of the metabolite was unequivocally identified by comparing the retention time as well as the mass spectrum with those of authentic compound, which was synthesized from swertiamarin (1). The transformation of swertiamarin to nitrogen-containing metabolite gentiandiol (3) in vivo was verified for the first time. Understanding of this unique metabolic pathway may shed light on clinical efficacy of swertiamarin (1) and will also assist in studies for the metabolism of other natural iridoids in vivo.

Antioxidant and antiviral activities of lipophilic epigallocatechin gallate (EGCG) derivatives

The water soluble green tea polyphenol epigallocatechin gallate (EGCG) was lipophilised by esterification with different fatty acids for expanded applications. Four lipophilic ester derivatives of EGCG, namely EGCG-O-tetrastearate, EGCG-O-tetraeicosapentaenoate, EGCG-O-tetradocosahexaenoate, and EGCG-O-octabutyrate, were prepared and evaluated for their antioxidant and antiviral activities in vitro. Incorporation of fatty acids, especially the long chain polyunsaturated fatty acids (PUFA), into EGCG resulted in increased peroxyl radical scavenging activity, as measured by ORAC (oxygen radical absorbance capacity) assay, and metal chelation capacity. However, the esters exhibited decreased reducing power. Antiviral activities of EGCG derivatives were remarkably higher than the parent EGCG molecule, which showed relatively weak effects. The EGCG–PUFA esters were 1700-fold more effective in inhibiting hepatitis C virus (HCV) protease than the positive control embelin. The derivatives also acted as α-glucosidase inhibitors, suggesting their potential in anti-HIV (human immunodeficiency virus) treatment. The results suggest that ester derivatives of EGCG with improved bioactivities may serve as excellent functional food ingredients and natural health products. Moreover, the omega-3 PUFA in the derivatives may also render additional or synergistic health benefits.

[Analysis of fatty acids from the flowers of Trollius chinensis]

OBJECTIVE

To analyze and identify fatty acids from the flowers of Trollius chinensis Bunge.

METHODS

To isolate and determine the constituents using GC/MS technique, quantitatively analyze their content by area normalization method.

RESULTS

31 fatty acids and 7 other constituents were isolated and determined.

CONCLUSION

The major fatty acids were hexadecanoic (19.85%), (Z,Z)-9,12-octadecadienoic (14.37%), tetradecanoic (13.93%), (Z)-9-octadecenoic (13.00%), dodecanoic (6.79%), 10-hydroxy-hexadecanoic (4.37%) and octadecanoic (3.34%) acids.

HCV protease inhibitory, cytotoxic and apoptosis-inducing effects of oleanolic acid derivatives

PURPOSE

To evaluate oleanolic acid derivatives on liver disease related bioactivities, 29 oleanolic acid derivatives of several series were tested for their inhibitory activity on hepatitis C viral protease and for their cytotoxic effects on Hep G2 cells.

RESULTS

The amino derivatives showed potent cytotoxicity, among which, the beta-amino isomer exhibited more distinct cytotoxicity than the alpha-isomer. The cytotoxicity of hemiesters and hemiamides varied as the chain lengths varied. The oxalic and malonic hemiesters showed weaker cytototoxicity than oleanolic acid, while those with longer chain lengths showed higher cytotoxicity. Contrary to the cytotoxic activity, the free amino derivatives showed little inhibitory activity on HCV protease. All the hemiesters and hemiamides showed high activity against HCV protease.

CONCLUSION

The findings that addition of amino-group enhanced the cytotoxicity and that introduction of acidic group increased the inhibition on HCV protease may be useful for further design and synthesis of triterpene derivatives as drug candidates for liver diseases.

Metabolism of isorhynchophylline in rats detected by LC-MS

PURPOSE This paper investigates the metabolic fate of isorhynchophylline (ISOR) as a main bioactive oxindole alkaloid in the traditional Chinese medicine. METHODS After oral administration of ISOR to rats, plasma, bile, urine and feces were analyzed by LC-MS. Hydroxylation of ISOR and successive glucuronidation proceeded in vitro by incubation with rat liver microsomes. RESULTS ISOR was identified in plasma, 11-hydroxyisorhynchophylline 11-O--D-glucuronide (MI1) and 10-hydroxyisorhynchophylline 10-O--D-glucuronide (MI2) in bile, and free 11-hydroxyisorhynchophylline (MI3) and 10-hydroxyisorhynchophylline (MI4) in urine and feces. Within 24 h, 71.6% of ISOR was excreted into the feces (in 20.0 g) and 13.8% into the urine (in 20.0 ml) of rats after oral administration of 37.5 mg/kg. Monitoring by LC-MS showed that 8.5% of ISOR was metabolized to MI3 and MI4 in a ratio of ca. 1:1. Specific inhibition of CYP isozymes indicated that CYP2D, CYP1A1/2 and CYP2C participate in ISOR hydroxylation. CONCLUSIONS ISOR was involved in the circulatory system after oral administration. Cytochrome P450 (CYP) in rat liver microsomes played a key role in ISOR hydroxylation.

Inhibition of the dimerization and active site of HIV-1 protease by secondary metabolites from the Vietnamese mushroom Ganoderma colossum

A new farnesyl hydroquinone, ganomycin I (1), was isolated along with ganomycin B (2) from the chloroform extract of the fruiting bodies of the Vietnamese mushroom Ganoderma colossum. These compounds inhibited HIV-1 protease with IC50 values of 7.5 and 1.0 microg/mL, respectively. Kinetic studies using Zhang-Poorman and Lineweaver plots revealed that compound 2 competitively inhibited the active site of the enzyme, whereas the tetracyclic triterpene schisanlactone A, previously isolated from the same fungus, was a dimerization inhibitor, with an IC50 value of 5.0 microg/mL. The previous findings were also confirmed by the virtual docking of both compounds with HIV-1 protease crystal structure.

Triterpene-farnesyl hydroquinone conjugates from Ganoderma sinense

Three new lanostane-type triterpenoids having farnesyl hydroquinone moieties, named ganosinensins A-C (1-3), were isolated from the fruiting body of Ganoderma sinense, together with three known lanostane triterpenes, ganodermanontriol, ganoderiol A, and ganoderiol D. The structures of compounds 1-3 were determined by spectroscopic data interpretation.

Synthesis and evaluation of A-seco type triterpenoids for anti-HIV-1protease activity

2,3-Seco-dioic acids derived from four different triterpene skeletons were prepared and evaluated for their anti-HIV-1 protease activity. Two A-seco derivatives showed potent inhibitory activity against HIV-1 protease (3c and 3e, IC(50) 5.7 and 3.9 microM, respectively), while four other derivatives showed moderate to weak inhibition (3a, 3b, 3d and 3f, IC(50) 15.7-88.1 microM). The combination of a 2,3-seco-2,3-dioic acid functional group in ring A and a free acid group at C-28 or C-30 significantly enhanced HIV-1 protease inhibitory activity (3a, 3c-3e, IC(50) 3.9-17.6 microM). On the other hand, all A-seco derivatives were found to be very weak inhibitors of HCV, renin and trypsin proteases (IC(50)>80 microM). These findings indicate that A-seco triterpenes with a carboxyl group at C-28 or C-30 are novel and highly selective HIV-1 protease inhibitors.

Inhibitory effects of antrodins A-E from Antrodia cinnamomea and their metabolites on hepatitis C virus protease

Antrodia cinnamomea is a highly valued folk medicine used for liver cancer, a disease often caused by the long term infection of hepatitis C virus (HCV). In the present study, the maleic and succinic acid constituents (antrodins A-E) of this medicinal fungus, the in vivo metabolites of antrodin C and the analogue of one of the metabolites were tested for their inhibitory activity on HCV protease. Most of the compounds showed potent inhibitory activity, with antrodin A being the most potent (IC(50) = 0.9 microg/mL). Antrodin A was isolated as one of the constituents of A. cinnamomea and was also detected as an in vivo metabolite of the major constituent antrodin C. The mode of inhibition for antrodin A on HCV protease was revealed by a Lineweaver-Burk plot as competitive inhibition. These results strongly support the use of this folk medicine for liver cancer and HCV infection which is a global problem.