Immunomodulatory, cyto-genotoxic, and growth regulatory effects of nerolidol on melon fruit fly, Zeugodacus cucurbitae (Coquillett) (Diptera: Tephritidae).

Insects have evolved a robust immune system consisting of humoral and cellular branches and their orchestrated response enables insect to defend against exogenous stressors. Exploration of underlying immune mechanisms of insect pest under allelochemical stress can give us new insights on insect pest management. In this study, nerolidol, a plant sesquiterpene was evaluated for its insecticidal, growth regulatory, immunomodulatory, and cyto-genotoxic effects against melon fruit fly, Zeugodacus cucurbitae (Coquillett). First, second, and third instar larvae of Z. cucurbitae were fed on artificial diet containing different concentrations (5, 25, 125, 625, and 3125 ppm) of nerolidol. Results revealed a significant reduction in pupation and adult emergence as well as prolongation of developmental duration of treated larvae. Decline in growth indices showed remarkable growth inhibitory effects of nerolidol. Pupal weight and nutritional parameters viz. Larval weight gain, food assimilated, and mean relative growth rate declined after treatment. Immunological studies on second instar larvae depicted a drop in total hemocyte count and variations in proportions of plasmatocytes and granulocytes of LC30 and LC50 treated larvae. Phenoloxidase activity in nerolidol treated larvae initially increased but was suppressed after 72 h of treatment. The frequency of viable hemocytes decreased and that of apoptotic and necrotic hemocytes increased with both the lethal concentrations of nerolidol. Comet assay revealed a significant damage to DNA of hemocytes. The findings of the current study indicate that nerolidol exerts its insecticidal action through growth regulation, immunomodulation, and cyto-genotoxicity thus revealing its potential to be used as biopesticide against Z. cucurbitae.

The genotoxic, cytotoxic and growth regulatory effects of plant secondary metabolite ß-caryophyllene on polyphagous pest Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae).

Use of secondary metabolites as an alternative to organic pesticides is an eco-friendly and safe strategy in pest management. ß-caryophyllene [(1R,4E,9S)-4,11,11-trimethyl-8-methylene bicyclo [7.2.0]undec-4-ene], a natural sesquiterpene is found as an essential oil in many plants like Syzygium aromaticum, Piper nigrum, Cannabis sativa. The present study aims at exploring the insecticidal, genotoxic and cytotoxic potential of ß-caryophyllene against common cutworm Spodoptera litura (Fab.), a major polyphagous pest. S. litura larvae were fed on different concentrations (5, 25, 125, 625 and 3125 ppm) of ß-caryophyllene. Results revealed delay in larval and pupal period with increase in concentration. Larval mortality increased and adult emergence declined significantly with increase in concentration. Higher concentrations of ß-caryophyllene caused pupal and adult deformities. A negative impact of ß-caryophyllene was also seen on the nutritional physiology of S. litura. Parameters such as relative growth rate, relative consumption rate, efficiency of conversion of ingested food, efficiency of conversion of digested food and approximate digestibility showed a significant reduction in a dose dependent manner. DNA damage assessed using comet assay revealed significant genotoxic effects at LC30 and LC50 concentrations. There was an increase in tail length, percent tail DNA, tail moment and olive tail moment. Phenol oxidase activity was suppressed at LC50 concentration with respect to control. Total hemocyte count also declined significantly at LC30 and LC50 concentrations as compared to control. ß-caryophyllene induced genotoxic and cytotoxic damage affecting the growth and survival of S. litura larvae. Our findings suggest that ß-caryophyllene has the potential to be used for the management of insect pests.

Selective Phytotoxic Effects of Sesquiterpenoids from Sonchus arvensis as a Preliminary Approach for the Biocontrol of Two Problematic Weeds of Wheat.

The objective of this study is to find new selective allelochemicals for managing two problematic weeds redroot pigweed (Amaranthus retroflexus) and common lambsquarters (Chenopodium album) with minimal negative effects on wheat, thereby facilitating the development of eco-friendly botanical herbicide. Three new sesquiterpenoids, sonarvenolide A-C (1-3), and nine known sesquiterpenoids (4-12) were isolated from Sonchus arvensis. Compound 1 was a rare peroxide-substituted eudesmane-type sesquiterpenoid, and compound 3 was a rare iphionane-type sesquiterpenoid. Notably, compounds 1, 3, 4, 6-8, and 11 showed selectivity phytotoxic activity. In particular, compounds 1, 3, and 4 exhibited excellent germination inhibitory effect on A. retroflexus (IC50 = 32.0-129.0 µM), higher than that of the positive control triasulfuron (IC50 = 141.7 µM), and compound 4 showed excellent inhibition on C. album (IC50 = 82.0 µM), higher than that of triasulfuron (IC50 = 100.9 µM). In addition, compounds 1, 3, and 4 showed allelopathy to the growth of two weeds, which were more potent than or close to that of triasulfuron. Furthermore, these compounds were not toxic to wheat even at a high concentration (1000 µM). Structure-activity relationships (SARs) revealed that the presence of peroxides or the absence of hydroxyl at C-5 in the eudesmane-type sesquiterpenoids could strengthen the inhibitory activities. The discovery of selective allelochemicals provides not only a new choice to control two problematic weeds of wheat but also new natural lead compounds for herbicides.

The sesquiterpenoid valerenic acid protects neuronal cells from the detrimental effects of the fungicide benomyl on apoptosis and DNA oxidation.

BACKGROUND: Valerenic acid (VA), a sesquiterpenoid of the plant Valeriana officinalis, has attracted attention of the research community due to its potential positive role against neurodegenerative diseases induced by chemicals. However, the relevant evidence in the literature is scarce. Therefore, this study aimed to examine the putative protective role of VA on the toxic effects of the fungicide benomyl on SH-SY5Y neural cells. METHODS: Cell viability was determined via the MTT and NRU assays, DNA damage was assessed via comet assay and apoptosis was evaluated through the expression of relevant genes. RESULTS: According to the results, exposure of the cells to benomyl enhanced viability inhibition and promoted DNA damage and apoptosis since the expression levels of the genes coding for MAPK8, NF-kB, Bax, Caspase-9 and Caspase-3 were increased. Treatment of the cells with VA ameliorated these effects in a concentration dependent manner. CONCLUSION: It is concluded that the molecular mechanism through which benomyl exerts its toxic action appears to depend on DNA oxidation and apoptosis induction. Furthermore, VA, a plant-derived compound is a protective antioxidant against pesticide-induced toxicity. Therefore, herbs, extracts and compounds of plant origin could be used as nutritional supplements that back up the beneficial role of medicine in neurodegenerative diseases.

Sesquiterpenoid-rich Essential Oils from Two Magnolia Plants: Contact and Repellent Activity to Three Stored-product Insects.

Stored products have been damaged by insects. Multiple approaches for pest management are employed. Among these approaches, botanical insecticide is an emerging one. This work investigated the pest management potential of Magnolia coriacea and Magnolia macclurei essential oils (EOs) to three major stored-product insects, namely the red flour beetle, cigarette beetle and booklouse. Magnolia coriacea and M. macclurei EOs showed promising contact toxicity to the cigarette beetle, with LD50 values of 11.7 and 12.3 µg/adult. The contact toxicity of M. coriacea EOs to the booklouse (LC50 = 95.5 µg/cm2) was much stronger than that of M. macclurei EOs (LC50 = 245.4 µg/cm2). To explore the contribution of individual compounds to insecticidal activity of EOs, chemical analysis was performed by GC-MS. Results showed that nerolidol (27.84%), agarospirol (18.34%), elixene (15.84%) and helminthogermacrene (12.69%) were major compounds of M. coriacea EOs, ß-guaiene (60.31%) and elixene (20.42%) dominated in M. macclurei EOs. Nerolidol and ß-guaiene showed contact activity to three insect species. Nerolidol showed stronger contact toxicity to the red flour beetle and cigarette beetle than M. coriacea EOs did, both samples were similar to the booklouse. ß-Guaiene was much stronger to the red flour beetle and booklouse, but weaker to the cigarette beetle than M. macclurei EOs did. The repellent effects of EOs and compounds were at various levels. Generally, results suggested that the contact toxic potential of samples could serve as management for the cigarette beetle and booklouse, while repellent effect would be used to control the red flour beetle.

Occurrence and stability of ptesculentoside, caudatoside and ptaquiloside in surface waters.

The illudane glycosides ptesculentoside (PTE), caudatoside (CAU) and ptaquiloside (PTA) are found in bracken ferns (Pteridium sp.). PTA is known to contaminate water bodies adjacent to bracken ferns and hence contribute to water toxicity. This study for the first time reports the presence of PTE and CAU in surface waters with concentrations up to 5.3 µg L-1 and outlines their stability under semi-natural conditions using water of two diverse lakes at their natural pH or pH adjusted to 6.5, with temperature controlled at 5 or 15 °C, and in the presence or absence of microbial activity. Under the same set of tested conditions the three illudane glycosides degraded at similar rates: with half-lives of approximately two days at pH 7.4 and 15 °C, and approximately 12 days at pH 5.2-6.5 and 5 °C. The water origin had significant influence on the degradation rates, but only due to its difference in pH. In most cases, the degradation rates of all the three illudane glycosides could be predicted using the existing first-order model for PTA hydrolysis. As PTE and CAU exhibit the same leaching pattern and stability as PTA, previous predictions of bracken environmental impact are likely underestimated, as PTE and CAU have not been monitored and included in the risk assessment.

New anti-influenza A viral norsesquiterpenoids isolated from feces-residing Streptomyces sp.

Three novel norsesquiterpenoids, (2R,4S,8aR)-8,8a,1,2,3,4-hexahydro-2-hydroxy-4,8a-dimethyl-2(2H)-naphthalenone (1), (1S,3S,4S,4aS,8aR)-4,8a-dimethyloctahydronaphthalene-1,3,4a(3H)-triol(2), (4S,4aS,8aS)-octahydro-4a-hydroxy-4, 8a-dimethyl-1(2H)-naphthalenone (3), as well as six other known analogues (4-9), were isolated from the culture broth of Streptomyces sp. XM17, an actinobacterial strain inhabiting the fresh feces of the giant panda Ailuropoda melanoleuca. The chemical structures of 1-3 were elucidated comprehensively by NMR spectroscopic and MS analyses, furthermore, the stereochemical configurations were resolved by NOESY experiments, along with ECD spectral and single-crystal X-ray crystallographic analyses. These compounds were then tested for their antiviral activities using the "pretreatment of virus" approach, which showed that most of these compounds were potent in inhibiting the entry of influenza A virus, with IC50 values ranging from 5 to 49 nM and selectivity indices all above 500.

The triterpenoids and sesquiterpenoids from the plant of Agrimonia pilosa.

A phytochemistry of the whole plant of Agrimonia pilosa led to the discovery of two new nortriterpenoids, agrimonorterpenes A and B (1 and 2), together with one known triterpenoid fupenzic acid (3) and seven known sesquiterpenoids (4-10). The new structures were determined as 19α-hydroxy-2-oxo-nor-A (3)-urs-11,12-dien-28-oic acid (1) and 2, 19ß-dihydroxy-3-oxo-23-noroleana-1, 4, 12-trien-28-oic acid (2) by the spectroscopic data of UV, IR, HR-ESI-MS, and NMR. Notably, the structure of 1 possessed a rare five-membered A- ring. And this is the first time to discover the sesquiterpenoids (4-10) from A. pilosa. Compound 3 displayed the selective cytotoxicity against HCT116, BGC823, and HepG2 cell lines with the IC50 values of 16.31 µM, 21.94 µM, and 23.40 µM, respectively.

New quinones, a sesquiterpene and phenol compounds with cytotoxic activity from the aerial parts of Morinda umbellata L.

Eight previously undescribed compounds, two quinones (1-2), one sesquiterpene (3), and five phenol compounds (4-8), including three enantiomers (6a, 7a, and 8a), along with three corresponding known enantiomers (6b-8b) were isolated from the aerial parts of Morinda umbellata L. Their structures were elucidated by 1D and 2D NMR spectroscopy, X-ray diffraction, and experimental and calculated ECD spectra, respectively. Compound 5 was found to have weak cytotoxity, which inhibited the growth of seven human cancer cell lines (A2780, HeLa, MCF-7, BGC-823, H7420, Ketr3 and SW 1990) with IC50 values from 13.3 to 15.1 µM.

A beta-glucosidase of an insect herbivore determines both toxicity and deterrence of a dandelion defense metabolite.

Gut enzymes can metabolize plant defense compounds and thereby affect the growth and fitness of insect herbivores. Whether these enzymes also influence feeding preference is largely unknown. We studied the metabolization of taraxinic acid ß-D-glucopyranosyl ester (TA-G), a sesquiterpene lactone of the common dandelion (Taraxacum officinale) that deters its major root herbivore, the common cockchafer larva (Melolontha melolontha). We have demonstrated that TA-G is rapidly deglucosylated and conjugated to glutathione in the insect gut. A broad-spectrum M. melolontha ß-glucosidase, Mm_bGlc17, is sufficient and necessary for TA-G deglucosylation. Using cross-species RNA interference, we have shown that Mm_bGlc17 reduces TA-G toxicity. Furthermore, Mm_bGlc17 is required for the preference of M. melolontha larvae for TA-G-deficient plants. Thus, herbivore metabolism modulates both the toxicity and deterrence of a plant defense compound. Our work illustrates the multifaceted roles of insect digestive enzymes as mediators of plant-herbivore interactions.

Plants produce certain substances to fend off attackers like plant-feeding insects. To stop these compounds from damaging their own cells, plants often attach sugar molecules to them. When an insect tries to eat the plant, the plant removes the stabilizing sugar, 'activating' the compounds and making them toxic or foul-tasting. Curiously, some insects remove the sugar themselves, but it is unclear what consequences this has, especially for insect behavior. Dandelions, Taraxacum officinale, make high concentrations of a sugar-containing defense compound in their roots called taraxinic acid ß-D-glucopyranosyl ester, or TA-G for short. TA-G deters the larvae of the Maybug ­ a pest also known as the common cockchafer or the doodlebug ­ from eating dandelion roots. When Maybug larvae do eat TA-G, it is found in their systems without its sugar. However, it is unclear whether it is the plant or the larva that removes the sugar. A second open question is how the sugar removal process affects the behavior of the Maybug larvae. Using chemical analysis and genetic manipulation, Huber et al. investigated what happens when Maybug larvae eat TA-G. This revealed that the acidity levels in the larvae's digestive system deactivate the proteins from the dandelion that would normally remove the sugar from TA-G. However, rather than leaving the compound intact, larvae remove the sugar from TA-G themselves. They do this using a digestive enzyme, known as a beta-glucosidase, that cuts through sugar. Removing the sugar from TA-G made the compound less toxic, allowing the larvae to grow bigger, but it also increased TA-G's deterrent effects, making the larvae less likely to eat the roots. Any organism that eats plants, including humans, must deal with chemicals like TA-G in their food. Once inside the body, enzymes can change these chemicals, altering their effects. This happens with many medicines, too. In the future, it might be possible to design compounds that activate only in certain species, or under certain conditions. Further studies in different systems may aid the development of new methods of pest control, or new drug treatments.

Toxic mechanisms and pharmacological properties of euptox A, a toxic monomer from A. adenophora.

A. adenophora (Spreng.) R.M. King & H. Rob. is as invasive plant known to cause toxicity in humans and animals. The plant's toxic activities have been associated with some toxic phytochemicals present in the plant. One of the major phytochemicals that have been reported to induce toxicity in various organs is euptox A (9-oxo-10, 11-dehydroageraphorone). Previous studies have reported that the main target organs of euptox A are the liver and spleen. Although, many studies have reported on euptox A toxicity in rats and mice, the mechanism of action and the beneficial uses of this toxin as well as it potential uses have not been fully established in literatures. Therefore, this review firstly, aims at elaborating on the toxic effects and mechanism of action of euptox A to give basic knowledge to researchers to help in the development of strategies that will reduce its toxicity to the environment. Secondly, this paper will also report on some beneficial uses of euptox A in recent years as well as suggest some future potential applications of this toxin to help in the utilization of this plant resource.

Curcumol inhibits encephalomyocarditis virus by promoting IFN-ß secretion.

BACKGROUND: Encephalomyocarditis virus (EMCV) infection can cause reproductive failure in sows and acute myocarditis and sudden death in piglets. It has caused huge economic losses to the global pig industry and that is why it is necessary to develop effective new treatment compounds. Zedoary turmeric oil has been used for treating myocarditis. Curcumol extracted from the roots of curcuma is one of the main active ingredient of zedoary turmeric oil. The anti-EMCV activity of curcumol along with the molecular mechanisms involved with a focus on IFN-ß signaling pathway was investigated in this study. METHOD: 3-(4,5-dimethyithiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the maximum non-toxic concentration (MNTC), 50% cytotoxic concentration (CC50), maximum inhibition rate (MIR) and 50% effective concentration (EC50) against EMCV. Through EMCV load, the anti-viral effect of curcumol was quantitatively determined using real-time quantitative PCR (qPCR). The effect of curcumol on the expression of IFN-ß was investigated using real-time quantitative PCR and ELISA. Western blot was used to determine the amounts of MDA5, MAVS, TANK, IRF3 and P-IRF3 proteins in human embryonic kidney 293 T (HEK-293 T) cells infected with EMCV. RESULTS: The results of MTT showed that compared with the ribavirin positive control group, the maximum inhibition ratio (MIR) of curcumol was greater but the selection index (SI) value was much smaller than that of ribavirin. The results of qPCR showed that curcumol and ribavirin significantly reduced the replication of EMCV in HEK-293 T cells. The curcumol (0.025 mg/mL) treatment has significantly increased IFN-ß mRNA expression in the EMCV-infected HEK-293 T cells while ribavirin treatment did not. The results of ELISA showed that curcumol (0.025 mg/mL and 0.0125 mg/mL) has significantly increased the expression of IFN-ß protein in EMCV-infected HEK-293 T cells. The results of Western blot showed that curcumol can inhibit the degradation of TANK protein mediated by EMCV and promote the expression of MDA5 and P-IRF3, while the protein expression level of MAVS and IRF3 remain unchanged. CONCLUSION: Curcumol has biological activity against EMCV which we suggest that IFN-ß signaling pathway is one of its mechanisms.

Synthesis of Pertyolides A, B, and C: A Synthetic Procedure to C17-Sesquiterpenoids and a Study of Their Phytotoxic Activity.

C17-sesquiterpenoids are a group of natural products that have been recently discovered. These compounds have the peculiarity of lacking the α,ß-methylene butyrolactone system, which is known to be quite relevant for many of the biological activities reported for sesquiterpene lactones. Unfortunately, the biological interest of C17-sesquiterpenoids has not been studied in-depth, mainly due to the poor isolation yields in which they can be obtained from natural sources. Therefore, in order to allow a deeper study of these novel molecules, we have worked out a synthetic pathway that provides C17-sesquiterpenoids in enough quantities from easily accessible sesquiterpene lactones to enable a more thorough investigation of their bioactivities. With this synthesis method, we have successfully synthesized, for the first time, three natural C17-sesquiterpenoids, pertyolides A, B, and C, with good overall yields. Furthermore, we have also evaluated their phytotoxicity against etiolated wheat coleoptiles and corroborated that pertyolides B and C present strong phytotoxic activity.

Antiproliferative Illudalane Sesquiterpenes from the Marine Sediment Ascomycete Aspergillus oryzae.

The new asperorlactone (1), along with the known illudalane sesquiterpene echinolactone D (2), two known pyrones, 4-(hydroxymethyl)-5-hydroxy-2H-pyran-2-one (3) and its acetate 4, and 4-hydroxybenzaldehyde (5), were isolated from a culture of Aspergillus oryzae, collected from Red Sea marine sediments. The structure of asperorlactone (1) was elucidated by HR-ESIMS, 1D, and 2D NMR, and a comparison between experimental and DFT calculated electronic circular dichroism (ECD) spectra. This is the first report of illudalane sesquiterpenoids from Aspergillus fungi and, more in general, from ascomycetes. Asperorlactone (1) exhibited antiproliferative activity against human lung, liver, and breast carcinoma cell lines, with IC50 values < 100 µM. All the isolated compounds were also evaluated for their toxicity using the zebrafish embryo model.

Euptox A Induces G0 /GI arrest and apoptosis of hepatocyte via ROS, mitochondrial dysfunction and caspases-dependent pathways in vivo.

As a toxin of Ageratina adenophora (A. adenophora), euptox A (9-oxo-10, 11-dehydroageraphorone) is known to cause hepatotoxicity in animals. In this study, we examined the effects of euptox A on mouse liver cells and its underlying mechanisms for the first time. We found that euptox A induced liver cell cycle arrest and apoptosis in a dose-dependent manner mainly by mitochondria -related pathways, with the affected cells characterized by the appearance of DNA fragmentation, membrane blebbing, and chromatin condensation. The results showed that euptox A similarly induced hepatocyte G0 /GI arrest and apoptosis mainly by ROS accumulation and mitochondria-mediated and caspase-dependent pathways, elucidated by the loss of mitochondrial membrane potential, release of cytochrome C and AIF, activation of caspase-3/-9, Bax, as well as suppression of Bcl-2. This paper will provide new insights into the mechanisms involved in liver toxicity caused by euptox A in mice.

Isolinderalactone Induces Cell Death via Mitochondrial Superoxide- and STAT3-Mediated Pathways in Human Ovarian Cancer Cells.

The mortality rate of ovarian cancer (OC) worldwide increases with age. OC is an often fatal cancer with a curative rate of only 20-30%, as symptoms often appear after disease progression. Studies have reported that isolinderalactone (ILL), a furanosesquiterpene derivative extracted from the dried root of Lindera aggregata, can inhibit several cancer cell lines' growth. However, the molecular mechanisms underlying ILL activities in human OC cells remain unexplored. This study investigated the antitumor activities of ILL in human OC cells by inducing mitochondrial superoxide (mtSO) and JAK-signal transducer and activator of transcription 3 (STAT3)-dependent cell death. ILL caused cell death in SKOV-3 and OVCAR-3 cells and increased the cell proportion in the subG1 phase. Additionally, ILL significantly induced mtSO production and reduced ROS production. Moreover, ILL downregulated mitochondrial membrane potential and the expression levels of anti-apoptotic Bcl-2 family proteins and superoxide dismutase (SOD)2. Results showed that ILL decreased phosphorylation of serine 727 and tyrosine 705 of STAT3 and expression of survivin, a STAT3-regulated gene. Furthermore, ILL-induced cell death was reversed by pretreatment of Mito-TEMPO, a mitochondria-specific antioxidant. These results suggest that ILL induces cell death by upregulation of mtSO, downregulation of mitochondrial SOD2, and inactivation of the STAT3-mediated pathway.

In vitro study on aspects of molecular mechanisms underlying invasive aspergillosis caused by gliotoxin and fumagillin, alone and in combination.

Gliotoxin (GT) and fumagillin (FUM) are mycotoxins most abundantly produced by Aspergillus fumigatus during the early stages of infection to cause invasive aspergillosis (IA). Therefore, we hypothesized that GT and FUM could be the possible source of virulence factors, which we put to test adopting in vitro monoculture and the novel integrated multiple organ co-culture (IdMOC) of A549 and L132 cell. We found that (i) GT is more cytotoxic to lung epithelial cells than FUM, and (ii) GT and FUM act synergistically to inflict pathology to the lung epithelial cell. Reactive oxygen species (ROS) is the master regulator of the cytotoxicity of GT, FUM and GT + FUM. ROS may be produced as a sequel to mitochondrial damage and, thus, mitochondria are both the source of ROS and the target to ROS. GT-, FUM- and GT + FUM-induced DNA damage is mediated either by ROS-dependent mechanism or directly by the fungal toxins. In addition, GT, FUM and GT + FUM may induce protein accumulation. Further, it is speculated that GT and FUM inflict epithelial damage by neutrophil-mediated inflammation. With respect to multiple organ cytotoxicity, GT was found to be cytotoxic at IC50 concentration in the following order: renal epithelial cells < type II epithelial cells < hepatocytes < normal lung epithelial cells. Taken together, GT and FUM alone and in combination contribute to exacerbate the damage of lung epithelial cells and, thus, are involved in the progression of IA.

Osteopontin siRNA does not confer resistance to toxic effects of parthenolide in Jurkat cells.

BACKGROUND: Osteopontin (OPN) plays a critical role in cell proliferation and drug resistance in cancer treatment and hematological malignancies. In T cell acute lymphoblastic leukemia, most initial therapies can induce remission while some patients then relapse and do not respond well to chemotherapy. The sesquiterpene lactone parthenolide (PTL) can induce apoptosis in a variety of cancer cell lines via inhibition of pro-inflammatory transcription factor nuclear factor kappa B and has anti-tumor activity in acute lymphoblastic leukemia treatment. AIM: To study the role of OPN in conferring in vitro resistance to PTL in Jurkat cells. METHODS: Jurkat cells were cultured with 8-20 µm PTL for 48 h. Transfection with OPN siRNA was provided. Apoptosis assays were performed with Annexin V-Alexa Fluor-488/PI. Quantitative real-time polymerase chain reaction was used to measure OPN gene expression using the 2-2-ΔΔCt method. RESULTS: PTL has cytotoxic and apoptotic effect on Jurkat cells with IC50 values of 16.1 µm, and growth inhibition effect of PTL does not differ significantly in combination with OPN-siRNA. OPN gene expression is not affected by PTL. CONCLUSIONS: Parthenolide induces apoptosis in Jurkat cells, but inhibition of osteopontin gene expression with siRNA does not reduce apoptotic effect of parthenolide.

Sesquiterpenoids and flavonoids from Inula viscosa induce programmed cell death in kinetoplastids.

Neglected tropical diseases such as leishmaniasis and American trypanosomiasis represent an increasing health problem. Current treatments are not satisfactory which remains an urgent need for novel, cheap and safe chemotherapies. In the course of our ongoing search for new potential anti-protozoal agents, this study aimed to perform a bio-guided fractionation of Inula viscosa (Asteraceae) using in vitro assays against three strains of Leishmania and Trypanosma genus. Eight known compounds were identified from the ethanolic extract of leaves, sesquiterpenoids (3 and 4) and flavonoids (5 and 6) were characterized as the main bioactive constituents. Sesquiterpene lactones 3 and 4 (IC50 values between 4.99 and 14.26 µM) showed promising antiparasitic activity against promastigotes of L. donovani, L. amazonensis and epimastigotes of T. cruzi. Their structures were successfully characterized by spectroscopic techniques including 1D and 2D NMR experiments. Furthermore, the main bioactive compounds 4, 5 and 6 displayed higher potency (IC50 values between 0.64 and 2.13 µM) against amastigotes of L. amazonensis than miltefosine (IC50 3.11 µM), and a low toxicity on macrophages cell line (SI > 45). The analysis of structure-activity relationship (SAR) of the anti-protozoal activity revealed that lactonization or oxidation enhanced the biological profile, suggesting that the hydrophobic moiety was presumably involved in the activity by increasing the affinity and/or cell membrane permeability. In order to get an insight into the mechanism of action of these compounds, programmed cell death (PCD) experiments were performed, and the obtained results suggest that the reported compounds induced PCD in the treated parasites. These results highlight that sesquiterpenoids and flavonoids from I. viscosa could constitute an interesting scaffold for the development of novel antikinetoplastid agents.

FEMA GRAS assessment of natural flavor complexes: Lavender, Guaiac Coriander-derived and related flavoring ingredients.

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a program for the re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, fifth in the series, evaluates the safety of NFCs containing linalool and/or other characteristic mono- and sesquiterpenoid tertiary alcohols and esters using the safety evaluation procedure published by the FEMA Expert Panel in 2005 and updated in 2018. The procedure relies on a complete chemical characterization of the NFC intended for commerce and organization of the chemical constituents of each NFC into well-defined congeneric groups. The safety of each NFC is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on absorption, metabolism and toxicology of both the constituent congeneric groups and the NFCs. Sixteen NFCs, derived from the Lavandula, Aniba, Elettaria, Daucus, Salvia, Coriandrum, Ribes, Guaiacum/Bulnesia, Citrus, Pogostemon, Melaleuca and Michelia genera, were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavor ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.