Transcriptome analysis to reveal the mechanism of the effect of Echinops latifolius polysaccharide B on palmitate-induced insulin-resistant.

Hepatic insulin resistance is a crucial pathological process in type 2 diabetes mellitus (T2DM) associated with visceral adiposity and metabolic disorders. Echinops latifolius polysaccharide B (ETPB), a polysaccharide extracted from Echinops latifolius Tausch, increases insulin sensitivity in the high-fat diet-fed and STZ induced SD rat model and even prevented hepatic metabolic disorders. However, the mechanism by which ETPB improves carbohydrate and lipid metabolisms in the liver with insulin resistance remains largely unknown. In the present work, an lnsulin resistance cell model (IR-HepG2) was established. Glucose consumption, glycogen content, triglycerides (TG), and free fatty acids (FFAs) levels were detected. The result revealed that the intervention of ETPB significantly increased glucose consumption and glycogen synthesis and reduced FFAs and TG production in IR-HepG2 cells. Further, we also employed RNA-seq to identify differentially expressed miRNAs (DEMs) and mRNAs (DEGs) with a fold change of ≥ 1.5 and p-value of <0.05. Finally, we identified 1028, 682, 382, 1614, 519 and 825 DEGs, and 71, 113, 94, 68, 52 and 38 DEMs in different comparisons, respectively. Based on a short time-series expression miner (STEM) analysis, six profiles were chosen for further analysis. Seventeen insulin resistance-associated dynamic DEGs were identified during ETPB stimulation. Based on these dynamic DEGs, the related miRNAs were acquired from DEMs, and an integrated miRNA-mRNA regulatory network was subsequently constructed. Besides, some DEGs and DEMs were validated using qPCR. This study provides transcriptomic evidence of the molecular mechanism involved in HepG2 insulin resistance, leading to the discovery of miRNA-based target therapies for ETPB.

Pharmacological Evaluation of Antipyretic and Antioxidant Activities of 80% Methanol Root Extract and Derived Solvent Fraction of Echinops kebericho M. (Asteraceae) in Mice Model.

BACKGROUND: Toxicity and untoward effects are very ostensible in most standard drugs including antipyretic agents. Searching for conceivable antipyretic drugs with minimal toxicities and side effects from traditional plants is a growing concern to date. Echinops kebericho M. (Asteraceae) is one of the most prominent traditional medicinal plants, which is frequently testified for its traditionally claimed uses of treating fever and different infectious and noninfectious disorders by traditional healers in Ethiopian folk medicine. However, this plant has not been scientifically assessed for its traditionally claimed uses. This study therefore is aimed at investigating the antipyretic and antioxidant activities of 80% methanol root extract and the derived solvent fraction of Echinops kebericho M. in mouse models. METHODS: Successive solvent maceration with increased polarity was used as the method of extractions, and chloroform, ethyl acetate, methanol, and water were used as solvents. After extraction, the crude extract and its derived solvent fractions were assessed for their antipyretic activities using yeast-induced pyrexia while, the antioxidant activities were measured in vitro using the diphenyl-2-picrylhydrazyl (DPPH) assay method. Both the extract and solvent fractions were evaluated at the doses of 100, 200, and 400 mg/kg for its antipyretic activities, and the antioxidant activity was evaluated at the doses of 50, 100, 200, 400, 600, 800, and 1000 mg/kg. The positive control group was treated with standard drug (ASA 100 mg/kg), while normal saline-receiving groups were assigned as negative control. RESULT: E. kebericho crude extract along with its derived solvent fractions showed statistically significant (p < 0.05, 0.01, and 0.001) temperature reduction activities. The maximum percentage of temperature reduction was observed by the highest dose (400 mg/kg) of the crude extract. The aqueous fraction also showed significantly (p < 0.05 and 0.01) higher temperature reduction than those of ethyl acetate and chloroform fractions. The free radical scavenging activities of the crude extract were also significantly high at the maximum dose, and the aqueous fraction showed the significantly highest antioxidant activity. CONCLUSION: In general, the data obtained from the present study clarified that the extract possessed significant antipyretic and antioxidant activities, upholding the traditionally claimed use of the plant.

Novel Bithiophene Dimers from Echinops latifolius as Potential Antifungal and Nematicidal Agents.

Three novel dimeric bithiophenes, echinbithiophenedimers A-C (1-3), along with two known thiophenes, 4 and 5, were obtained from Echinops latifolius, and their structures were identified through extensive spectroscopic analysis and electronic circular dichroism calculations. Compounds 1-3 possessed new carbon skeletons; they are dimeric bithiophenes with 1 and 2 featuring an unprecedented 1,3-dioxolane ring system and 3 featuring an unusual 1,4-dioxane ring. These compounds are the first examples of bithiophene dimers furnished by different cyclic diethers. Dimeric bithiophenes 1-3 had good antifungal activities against five phytopathogenic fungi, and compound 3 showed excellent activity against Alternaria alternate and Pyricularia oryzae, with a minimal inhibitory concentration value of 8 µg/mL, which was close to or higher than that of carbendazim. Moreover, its effect on the mycelial morphology was observed by scanning electron microscopy. Compounds 1-3, which were demonstrated to be nonphototoxic thiophenes, exhibited better nematicidal activity than the commercial nematicide ethoprophos against Meloidogyne incognita. This study revealed that dimeric bithiophenes containing 1,3-dioxolane or 1,4-dioxane rings could be used as novel antifungal and nematicidal agents for controlling plant fungal and nematode pathogens.

Metabolomics profiling reveals Echinops latifolius Tausch improves the trabecular micro-architecture of ovariectomized rats mainly via intervening amino acids and glycerophospholipids metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: Echinops latifolius Tausch (ELT) is traditional Mongolian medicine in China, and often used to against osteoporosis, strengthen tendons and bones, clear bones heat. AIM OF THE STUDY: To study efficacy of ELT on ovariectomized (OVX) rats and underly metabolic pathways related to trabecular micro-architecture changing of OVX. MATERIALS AND METHODS: Three-month-old female Wistar rats were randomly divided into 4 groups (n = 6) including normal group (without surgery), sham group (bilateral laparotomy), OVX group (bilateral ovariectomy), and ELT-treated groups (ELT-treated after bilateral ovariectomy). The effects of ELT on trabecular micro-architecture and biochemical markers of OVX rat were investigated by dual-energy X-ray absorptiometry machine and Enzyme-linked immunosorbent assay (ELISA), respectively. Untargeted metabolomics strategy was applied to discover the potential biomarkers and related metabolic pathways involving the progression of OVX-induced osteoporosis. RESULTS: The trabecular micro-architecture and biochemical markers of OVX rats were improved by ELT. We found 36 potential biomarkers and 21 related metabolic pathways were involved in progression of OVX-induced osteoporosis. Amino acids metabolism and glycerophospholipids metabolism were mainly intervened in ELT treatment on ovariectomized rats. The disordered amino acids and glycerophospholipids metabolism closely related to the imbalance between bone resorption and formation were reversed by administration of ELT, indicating that the influences of ELT on OVX rats' trabecular micro-architecture may possible be associated with intervening amino acids and glycerophospholipids metabolism. CONCLUSIONS: This approach may provide the metabolomic perspective to link metabolic alterations and anti-osteoporosis action of ELT, to further explain how ELT works in postmenopausal patients with bone loss.

Thiophenes from Echinops grijsii as a Preliminary Approach To Control Disease Complex of Root-Knot Nematodes and Soil-Borne Fungi: Isolation, Activities, and Structure-Nonphototoxic Activity Relationship Analysis.

Naturally occurring thiophenes possess excellent nematicidal and fungicidal activities. However, thiophenes often have limited application in soil due to their light-dependent toxicity given the living and reproductive condition of soil-borne pathogens. In this study, six new (1-6) and six known thiophenes (7-12) were isolated from Echinops grijsii. Compounds 1-2, 4-5, 8-9, 11 , and 12 showed stronger nematicidal activity against Meloidogyne incognita than commercial nematicide abamectin. 4-10 were demonstrated as nonphototoxic thiophenes. Among these, 4 and 8 were the most potent thiophenes (LC50 values 2.57 and 0.91 µg/mL in light, 1.80 and 0.86 µg/mL in dark, respectively) against M. incognita. SAR revealed that thiophene skeleton was essential for nematicidal activity, while disubstituted groups were helpful for nonphototoxicity. Although an increased number of acetylenes improved activity, it decreased nonphototoxicity. Acyl groups could suppress the effects of light on activity, with the level of inhibitory effects depending on its number and chain length, while chlorine played important roles in promoting activity. Additionally, compounds 1-2, 4-5, 7, 8, and 10 displayed antifungal activity against six soil-borne fungi in various degrees. The discovery of nonphototoxic thiophenes and elucidation of SAR provide important information for the exploitation and utilization of thiophenes in the integrative management regarding disease complexes caused by the combination of root-knot nematode and soil-borne fungi.

Antidiabetic and antidyslipidemic potential of Echinops echinatus in rat models of type I and type II diabetes.

Echinops echinatus is traditionally an important plant that finds its extensive use as a diuretic, anti-inflammatory, anti-pyretic, nerve tonic, abortifacient, aphrodisiac, antiasthmatic, and antidiabetic agent. The current study investigates protection against the hyperglycemia and dyslipidemia in alloxan-induced (type I diabetes) and fructose-fed insulin resistance (type II diabetes) models of diabetes treated with aqueous methanolic root extract of E. echinatus (Ee.Cr). Albino rats were treated orally with Ee.Cr at doses 100, 300 and 500mg/kg. The fasting blood glucose was measured by glucometer, while standard kits were used to determine the levels of serum total cholesterol, triglycerides and HDL. The administration of Ee.Cr significantly (P<0.001) reduced the FBG concentration in a dose-dependent pattern in alloxan-induced and fructose-fed diabetic rats. The Ee.Cr also corrected the dyslipidemia associated with fructose and alloxan-induced diabetes by significantly (P<0.001) decreasing the concentration of serum total cholesterol, triglycerides, and LDL and by increasing HDL concentration. Ee.Cr also significantly (P<0.001) improved the glucose tolerance in fructose-fed rats. We conclude that Ee.Cr has antidiabetic and antidyslipidemic effects in both insulin-dependent alloxan-induced diabetes and fructose-induced insulin resistance diabetes rat models.

Biological activity of Echinops spinosus on inhibition of paracetamol-induced renal inflammation.

This study was designed to evaluate the possible mechanisms through which Echinops spinosus (ES) extract demonstrates nephroprotective effect on the paracetamol acetominophen (N-acetyl-p-aminophenol (APAP)) induced nephrotoxicity in rats. Twenty-four Swiss albino rats were divided into four groups (six rats each). The placebo group was orally administered sterile saline, the APAP group received APAP (200 mg·kg-1·day-1 i.p.) daily, the ES group was given ES extract orally (250 mg/kg), and the APAP + ES group received APAP as for the APAP group and administrated the ES extract as for the ES group. Pretreatment of methyl alcohol extract of ES reduced the protein expression of inflammatory parameters including cyclooxygenase-2 and nuclear factor κB in the kidney. It also reduced the mRNA gene expression of tumor necrosis factor-α and interleukin-1ß. The ES extract compensated for deficits in the total antioxidant activity, suppressed lipid peroxidation, and amended the APAP-induced histopathological kidney alterations. Moreover, ES treatment restored the elevated levels of urea nitrogen in the blood and creatinine in the serum by APAP. The ES extract attenuated the APAP-induced elevations in renal nitric oxide levels. We clarified that the ES extract has the potential to defend the kidney from APAP-induced inflammation, and the protection mechanism might be through decreasing oxidative stress and regulating the inflammatory signaling pathway through modulating key signaling inflammatory biomarkers.

Novel Substituted Thiophenes and Sulf-Polyacetylene Ester from Echinops ritro L.

Three new substituted bithiophenes (1⁻3), and one new sulf-polyacetylene ester, ritroyne A (16) were isolated from the whole plant of Echinops ritro together with twelve known substituted thiophenes. The structures were elucidated on the basis of extensive spectroscopic analysis including 1D and 2D NMR as well as MS. Furthermore, the absolute configuration of ritroyne A (16) was established by computational methods. In bioscreening experiments, four compounds (2, 4, 12, 14) showed similar antibacterial activity against Staphylococcus aureus ATCC 2592 with levofloxacin (8 µg/mL). Five compounds (2, 4, 9, 12, 14) exhibited antibacterial activities against Escherichia coli ATCC 25922, with minimum inhibitory concentration (MIC) values of 32⁻64 µg/mL. Three compounds (2, 4, 12) exhibited antifungal activities against Candida albicans ATCC 2002 with MIC values of 32⁻64 µg/mL. However, compound 16 did not exhibit antimicrobial activities against three microorganisms.

Mongolian Medicine echinops prevented postmenopausal osteoporosis and induced ER/AKT/ERK pathway in BMSCs.

Hormone replacement medicine such as traditional Chinese medicine has proven to be effective in decreasing the risk of osteoporosis. Mongolian medicine echinops prevents osteoporosis, but its mechanism remains unclear. In this study, we explored the mechanism underlying echinops prevents and treats postmenopausal osteoporosis. Osteoporosis model was established by ovariectomy in rats. Rats were treated to Echinops (16.26, 32.5, or 65 mg/kg/day) by oral gavage for 3 months. Bone mineral density (BMD) was detected by micro-CT detection of left proximal medial metaphyseal tibia. Hematoxylin and eosin (H&E) and toluidine blue O staining were also performed. Serum levels of E2, ALP and testosterone were examined. Bone marrow-derived bone marrow stem cells (BMSCs) were isolated and treated with echinops-containing serum. Estrogen receptors (ER) including ERα and ERß in bone specimens and BMSCs were detected by qRT-PCR. Cell viability and colon formation of BMSCs were detected. Expressions of ERα, ERß, AKT, p-AKT, ERK, and p-ERK in BMSCs were detected by western blot. Results showed that echinops significantly increased trabecular interconnectivity, thickness of trabeculae, and connection of trabecula. Echinops significantly increased BMD and E2, but significantly reduced ALP and testosterone in dose-dependent manners. Echinops induced ERα and ERß in both bone specimens and BMSCs. Echinops enhanced cell viability and ability of colony formation of BMSCs, and increased ERα, ERß, p-AKT, and p-ERK. Thus, Mongolian echinops reduced bone loss and delayed the occurrence and development of osteoporosis, and increased ERα, ERß, p-AKT, and P-ERK in BMSCs. These results provide experimental basis for clinical prevention and treatment of postmenopausal osteoporosis by echniops.

Phytochemical constituents and antioxidant activity of Echinops albicaulis.

Two thiophenes; 5-(3-buten-1-ynyl)-2,2'-bithiophene (2) and α-tertthienyl (9), two alkaloids; echinopsine (10) and echinorine (11), three flavonoids; genkwanin (5), apigenin (6), and rutin (7), two triterpenoids; lupeol acetate (1) and lupeol linoleate (4), together with 2,6,10-trimethyldodeca-2,6,10-triene (4) and ß-sitosterol glucoside (8) were isolated from the aerial parts of Echinops albicaulis. Antioxidant, antimicrobial and antiprotozoal activities were evaluated. E. albicaulis aqueous methanolic extract (50, 10, and 1 mg/mL) showed significant antioxidant activity comparable to the potent antioxidant, N-acetyl cysteine, moreover, the aqueous methanolic extract (1 mg/mL) significantly reduced intracellular reactive oxygen species in active cell cultures of human peripheral blood mononuclear cells under oxidative stress more than the reference antioxidant N-acetyl cysteine. None of the isolated compounds showed antimicrobial or antiprotozoal activities at concentration up to 20 µg/mL.

Antimalarial Activity of Acetylenic Thiophenes from Echinops hoehnelii Schweinf.

Malaria is one of the world's most severe endemic diseases and due to the emergence of resistance to the currently available medicines, the need for new targets and relevant antimalarial drugs remains acute. The crude extract, four solvent fractions and two isolated compounds from the roots of Echinops hoehnelii were tested for their antimalarial activity using the standard four-day suppressive method in Plasmodium berghei-infected mice. The 80% methanol extract exhibited suppression of 4.6%, 27.8%, 68.5% and 78.7% at dose of 50, 100, 200 and 400 mg/kg respectively. The dichloromethane fraction displayed chemosuppression of 24.9, 33.5 and 43.0% dose of 100, 200 and 400 mg/kg of body weight. Five acetylenicthiophenes were isolated from the dichloromethane fraction of which 5-(penta-1,3-diynyl)-2-(3,4-dihydroxybut-1-ynyl)-thiophene decreased the level of parasitaemia by 43.2% and 50.2% while 5-(penta-1,3-diynyl)-2-(3-chloro-4-acetoxy-but-1-yn)-thiophene suppressed by 18.8% and 32.7% at 50 and 100 mg/kg, respectively. The study confirmed the traditional claim of the plant to treat malaria and could be used as a new lead for the development of antimalarial drugs.

Identification of Larvicidal Constituents of the Essential Oil of Echinops grijsii Roots against the Three Species of Mosquitoes.

The screening of Chinese medicinal herbs for insecticidal principles showed that the essential oil of Echinops grijsii Hance roots possessed significant larvicidal activity against mosquitoes. The essential oil was extracted via hydrodistillation and its constituents were determined by gas chromatography-mass spectrometry (GC-MS) analysis. GC-MS analyses revealed the presence of 31 components, with 5-(3-buten-1-yn-1-yl)-2,2'-bithiophene (5-BBT, 27.63%), αterthienyl (α-T, 14.95%),1,8-cineole (5.56%) and cis-ß-ocimene (5.01%) being the four major constituents. Based bioactivity-directed chromatographic separation of the essential oil led to the isolation of 5-BBT, 5-(4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (5-IBT) and αT as active compounds. The essential oil of E. grijsii exhibited larvicidal activity against the fourth instar larvae of Aedes albopictus, Anopheles sinensis and Culex pipiens pallens with LC50 values of 2.65 µg/mL, 3.43 µg/mL and 1.47 µg/mL, respectively. The isolated thiophenes, 5-BBT and 5-IBT, possessed strong larvicidal activity against the fourth instar larvae of Ae. albopictus(LC50 = 0.34 µg/mL and 0.45 µg/mL, respectively) and An. sinensis(LC50 = 1.36 µg/mL and 5.36 µg/mL, respectively). The two isolated thiophenes also had LC50 values against the fourth instar larvae of C. pipiens pallens of 0.12 µg/mL and 0.33 µg/mL, respectively. The findings indicated that the essential oil of E. grijsii roots and the isolated thiophenes have an excellent potential for use in the control of Ae.albopictus, An. sinensis and C. pipiens pallens larvae and could be used in the search for new, safer and more effective natural compounds as larvicides.

Dimeric sesquiterpene and thiophenes from the roots of Echinops latifolius.

Phytochemical investigation of the roots of Echinops latifolius led to the isolation of a new carbon skeleton dimeric sesquiterpene (1) and a new thiophene (2), along with six known compounds (3-8). Their structures and relative stereochemistry were elucidated by spectroscopic and spectrometric methods (1H and 13C NMR, COSY, HSQC, HMBC, ROESY, and MS). All isolates were evaluated for their inhibition of LPS-induced NO production in RAW 264.7 cells. Compounds 4 and 5 exhibited the most potent inhibitory effects on NO production.

ANTIMICROBIAL ACTIVITY OF Echinops kebericho AGAINST HUMAN PATHOGENIC BACTERIA AND FUNGI.

BACKGROUND: Traditional medicine remains the primary source of health care in developing countries. Echinops kebericho Mesfin is a well known endemic medicinal plant in Ethiopia and is traditionally used to treat both infectious and non-infectious diseases. The aim of this study was to evaluate antibacterial and antifungal activities of water, ethanol and methanol based crude extracts of E. kebericho Mesfin against selected human pathogenic bacteria and fungi. MATERIALS AND METHODS: Crude extracts of E. kebericho Mesfin were prepared by maceration method. Disc diffusion assay of the extracts was carried out in four different concentrations against three different bacterial species and two clinically isolated fungal species. Agar dilution method was used to determine minimum inhibitory concentration, minimum bactericidal and fungicidal concentrations of the extracts. RESULTS: Water based extracts exhibited the lowest antimicrobial activity when compared the ethanol and methanol based extracts (P< 0.05). Among the tested microorganisms, S. aureus, C. albicans and A. flavus were the most sensitive to alcohol based extracts. The minimum inhibitory concentration of the alcohol based extract ranged from 3.12 to 25µg/ml while those of the water based extracts were 100µg/ml and above. The lowest bactericidal and fungicidal concentrations of the ethanol and methanol based extracts were observed to be 6.25µg/ml against S. aureus and C. albicans and 37.5µg/ml against E. coli. CONCLUSIONS: The traditional use of E. kebericho by local people in treating various types of infectious and non-infectious diseases was supported by this study. Antimicrobial activity of the medicinal plant varied with those of extraction solvents and against tested microorganisms.

Formal Total Synthesis of Echinopines A and B via Cr(0)-Promoted [6π + 2π] Cycloaddition.

A concise formal synthesis of echinopines A and B is reported. The key [5.5.7] tricyclic intermediate, which has been previously used for the synthesis of echinopine A and B, was assembled using Cr(0)-promoted photochemical [6π + 2π] cycloaddition followed by a radical cyclization step.

[Treatment of rheumatoid arthritis with flavonoids of Echinps latifolius Tausch in rat model].

OBJECTIVE: To investigate the effect of Flavonoids extracted from Echinps latifolius Tausch(FELT) on rheumatoid arthritis (RA) in rat model. METHOD: Fifty SD rats were randomly divided into model group, control group, and low, medium, and high-dose FELT groups (n=10 in each group). Complete Freund's adjuvant (0.1 mL) was used to induce RA in rats. FELT in doses of 50 mg/kg, 100 mg/kg, 150 mg/kg was given to rats in low, medium and high-dose FELT groups by gavage, and same volume of PBS was given to rats in control group. The arthritis score and the paw swelling score were measured to evaluate the therapeutic effect of FELT. Real time qPCR was used to detect the mRNA expression of fibronectin and MMP3 in synovial tissue and the mRNA expression of caspase 3, Bcl-2 and Bcl-2 associated X protein (Bax) in fibroblast-like synoviocytes (FLS). RESULTS: The arthritis score and the paw swelling score were significantly decreased in three FELT groups compared to RA model rats (P <0.05). The relative expression levels of FN and MMP3 mRNA in synovium of three FELT-treatment groups were significantly lower than those in model group (1.80, 1.76 and 1.67 vs 2.53; 1.69, 1.46 and 1.45 vs 2.67, respectively, all P <0.05). The relative expression levels of Bax and caspase 3 mRNA in FLSs of three FELT groups were higher than those in model group (0.56, 0.58 and 0.60 vs 0.30; 0.54, 0.56 and 0.59 vs 0.29, respectively, all P <0.05); while the relative expression levels of Bcl-2 mRNA in FELT groups were lower than that in model group (2.20, 2.08 and 2.08 vs 4.04, respectively, P <0.05). CONCLUSION: FELT may inhibit the synovium proliferation in RA model rats through promoting the FLS apoptosis.

A New Bithiophene from the Root of Echinops grijsii.

A new bithiophene, 5-(4-hydroxy-3-methoxy-1-butyny)-2,2'-bithiophene (1), and sixteen known thiophenes: 2-(3,4-dihydroxybut-1-ynyl)-5-(penta-1,3-diynyl)thiophene (2), α-terthienyl (3), 5-(3,4-dihydroxybut-1-ynyl)-2,2'-bithiophene (4), 5-acetyl-2,2'-bithiophene (5), 5-formyl-2,2'-bithiophene (6), methyl 2,2'-bithiophene-5-carboxylate (7), 5-(but-3-en-1-ynyl)-2,2'-bithiophene (8), 5-(4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (9), cardopatine (10), isocardopatine (11), 5-(3-hydroxy-4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (12), 5-(3-hydroxymethyl-3-isovaleroyloxyprop-1-ynyl)-2,2'-bithiophene (13), 5-(4-hydroxy-1-butynyl)-2,2'-bithiophene (14), 5-(4-acetoxy-1-butynl)-2,2'-bithiophene (15), 2,2'-bithiophene-5-carboxylic acid (16) and 2-(4-hydroxybut-1-ynyl)-5-(penta-1,3-diynyl)thiophene (17) were isolated from the roots of Echinops grjisii Hance. Among them, compounds 6, 7 and 16 were isolated from a natural source for the first time. Compounds 2, 4 and 14 exhibited significant anti-inflammatory activity against nitrite of LPS-stimulated production in the RAW 264.7 cell line.

Toxicity of thiophenes from Echinops transiliensis (Asteraceae) against Aedes aegypti (Diptera: Culicidae) larvae.

Structureactivity relationships of nine thiophenes, 2,2': 5',2″-terthiophene (1), 2-chloro-4-[5-(penta-1,3-diyn-1-yl)thiophen-2-yl]but-3-yn-1-yl acetate (2), 4-(2,2'-bithiophen-5-yl)but-3-yne-1,2-diyl diacetate (3), 4-[5-(penta-1,3-diyn-1-yl)thiophen-2-yl]but-3-yne-1,2-diyl diacetate (4), 4-(2,2'-bithiophen-5-yl)-2-hydroxybut-3-yn-1-yl acetate (5), 2-hydroxy-4-[5-(penta-1,3-diyn-1-yl)thiophen-2-yl]but-3-yn-1-yl acetate (6), 1-hydroxy-4-[5-(penta-1,3-diyn-1-yl)thiophen-2-yl]but-3-yn-2-yl acetate (7), 4-(2,2'-bithiophen-5-yl)but-3-yne-1,2-diol (8), and 4-[5-(penta-1,3-diyn-1-yl)thiophen-2-yl]but-3-yne-1,2-diol (9), isolated from the roots of Echinops transiliensis, were studied as larvicides against Aedes aegypti. Structural differences among compounds 3, 5, and 8 consisted in differing AcO and OH groups attached to C(3″) and C(4″), and resulted in variations in efficacy. Terthiophene 1 showed the highest activity (LC50 , 0.16 µg/ml) among compounds 1-9, followed by bithiophene compounds 3 (LC50 , 4.22 µg/ml), 5 (LC50 , 7.45 µg/ml), and 8 (LC50 , 9.89 µg/ml), and monothiophene compounds 9 (LC50 , 12.45 µg/ml), 2 (LC50 , 14.71 µg/ml), 4 (LC50 , 17.95 µg/ml), 6 (LC50 , 18.55 µg/ml), and 7 (LC50 , 19.97 µg/ml). These data indicated that A. aegypti larvicidal activities of thiophenes increase with increasing number of thiophene rings, and the most important active site in the structure of thiophenes could be the tetrahydro-thiophene moiety. In bithiophenes, 3, 5, and 8, A. aegypti larvicidal activity increased with increasing number of AcO groups attached to C(3″) or C(4″), indicating that AcO groups may play an important role in the larvicidal activity.

Cytotoxicity and modes of action of four Cameroonian dietary spices ethno-medically used to treat cancers: Echinops giganteus, Xylopia aethiopica, Imperata cylindrica and Piper capense.

ETHNOPHARMACOLOGICAL RELEVANCE: Echinops giganteus, Imperata cylindrica, Piper capense and Xylopia aethiopica are four medicinal spices used in Cameroon to treat cancers. AIM OF THE STUDY: The above plants previously displayed cytotoxicity against leukemia CCRF-CEM and CEM/ADR5000 cell lines as well as human pancreatic MiaPaCa-2 cells. The present study aims at emphasizing the study of the cytotoxicity and the modes of action of the above plants on a panel of ten cancer cell lines including various sensitive and drug-resistant phenotypes. The study has been extended to the isolation of the bioactive constituents from Echinops giganteus. MATERIALS AND METHODS: The cytotoxicity of the extracts was determined using a resazurin reduction assay, whereas the caspase-Glo assay was used to detect the activation of caspases 3/7, caspase 8 and caspase 9 in cells treated with the four extracts. Flow cytometry was used for cell cycle analysis and detection of apoptotic cells, analysis of mitochondrial membrane potential (MMP) as well as measurement of reactive oxygen species (ROS). RESULTS: The four tested extracts inhibited the proliferation of all tested cancer cell lines including sensitive and drug-resistant phenotypes. Collateral sensitivity of cancer cells to the extract of Echinops giganteus was generally better than to doxorubicin. The recorded IC50 ranges were 3.29 µg/mL [against human knockout clones HCT116 (p53(-/-)) colon cancer cells] to 14.32 µg/mL (against human liver hepatocellular carcinoma HepG2 cells) for the crude extract from Echinops giganteus, 4.17 µg/mL (against breast cancer cells transduced with control vector MDA-MB231 cells) to 19.45 µg/mL (against MDA-MB-231 BCRP cells) for that of Piper capense, 4.11 µg/mL (against leukemia CCRF-CEM cells) to 30.60 µg/mL (against leukemia HL60AR cells) for Xylopia aethiopica, 3.28 µg/mL [against HCT116 (p53(-/-)) cells] to 33.43 µg/mL (against HepG2 cells) for Imperata cylindica and 0.11 µg/mL (against CCRF-CEM cells) to 132.47 µg/mL (against HL60AR cells) for doxorubicin. The four tested extracts induced apoptosis in CCRF-CEM cells via the alteration loss of MMP whilst that of Piper capense also enhanced the production of ROS. CONCLUSION: The studied plants are potential cytotoxic drugs that deserve more detailed exploration in the future, to develop novel anticancer drugs against sensitive and otherwise drug-resistant phenotypes.

Essential oils from the roots of Echinops bannaticus Rochel ex Schrad. and Echinops sphaerocephalus L. (Asteraceae): chemotaxonomic and biosynthetic aspects.

Herein, we report, for the first time, the results of detailed chemical and statistical analyses of the essential oils from the roots of two Echinops species (Asteraceae), E. bannaticus Rochel ex Schrad., and E. sphaerocephalus L., from the weed flora of Serbia. Among 106 and 81 constituents, respectively, S-containing polyacetylene compounds and triquinane sesquiterpenoids made up ca. 80% of the oils. Several of these compounds are reported here as new metabolites for the two species or even for the genus Echinops. A multivariate statistical comparison of the essential-oil composition data for these two and additional six taxa of this genus available from the literature permitted an examination of the mutual relationships of the taxa within this morphologically highly uniform genus. Principal component analysis (PCA) and agglomerative hierarchical clustering revealed a grouping of E. bannaticus and E. sphaerocephalus (both belonging to the section Echinops), and their close relationship with E. grijsii, suggesting a circumscription of this Chinese taxon to the section Echinops. PCA Correlation matrix offered valuable insight into the biosynthetic links between essential-oil constituents, and these agreed excellently with the currently proposed ones for the polyacetylene S-containing compounds, triquinanes, and monoterpenes.