MetaboLights
A pyrrolizine alkaloid that is seneciphylline in which the exocyclic double bond has been converted to the corresponding epoxide.
Identification
(3S,3'S,6R,14aR,14bR)-6-hydroxy-3',6-dimethyl-5-methylidene-5,6,9,11,13,14,14a,14b-octahydro-2H-spiro[1,6-dioxacyclododecino[2,3,4-gh]pyrrolizine-3,2'-oxirane]-2,7(4H)-dione
12-hydroxy-13,19-didehydro-15,20-dihydro-15,20-epoxysenecionan-11,16-dione
13,19-didehydrojacobine
Species
jacobaea ambigua
NCBI:txid189228 17913058
senecio aquaticus
NCBI:txid189230 11978435
jacobaea
NCBI:txid405757 10.1007/s11306-017-1184-0
jacobaea vulgaris.
NCBI:txid98722 21159354
Europe PubMed Central results
Alkaloids from Senecio aquaticus.
Author: Christov VS, Mikhova BP, Evstatieva LN.
Abstract: Erucifoline (1) and 9-angeloylhastanecine (2) were isolated from the aerial parts of Senecio aquaticus. Five other pyrrolizidine alkaloids were tentatively identified by GC/MS analysis: jacobine; seneciphylline; spartioidine; jacozine; and senecionine.
Pyrrolizidine alkaloid profiles of the Senecio cineraria group (Asteraceae).
Author: Tundis R, Loizzo MR, Statti GA, Passalacqua NG, Peruzzi L, Menichini F.
Abstract: Alkaloid profiles of five Senecio species (Asteraceae), including S. ambiguus subsp. ambiguus, S. ambiguus subsp. nebrodensis, S. gibbosus subsp. bicolor, S. gibbosus subsp. gibbosus, and S. gibbosus subsp. cineraria, were studied. Eleven pyrrolizidine alkaloids were identified and their content was evaluated by GLC-MS and GLC analysis. Otosenine and florosenine were found to be the major alkaloids in all studied species. It is interesting that only S. ambiguus subsp. nebrodensis was characterized by a high content of the alkaloids jacobine, jacoline, jaconine, and jacozine.
The genotype dependent presence of pyrrolizidine alkaloids as tertiary amine in Jacobaea vulgaris.
Author: Joosten L, Cheng D, Mulder PP, Vrieling K, van Veen JA, Klinkhamer PG.
Abstract: Secondary metabolites such as pyrrolizidine alkaloids (PAs) play a crucial part in plant defense. PAs can occur in plants in two forms: tertiary amine (free base) and N-oxide. PA extraction and detection are of great importance for the understanding of the role of PAs as plant defense compounds, as the tertiary PA form is known for its stronger influence on several generalist insects, whereas the N-oxide form is claimed to be less deterrent. We measured PA N-oxides and their reduced tertiary amines by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We show that the occurrence of tertiary PAs is not an artifact of the extraction and detection method. We found up to 50% of tertiary PAs in shoots of Jacobine - chemotype plants of Jacobaea vulgaris. Jacobine and its derivatives (jacoline, jaconine, jacozine and dehydrojaconine) may occur for more than 20% in reduced form in the shoots and more than 10% in the roots. For 22 PAs detected in F(2) hybrids (J. vulgaris × Jacobaea aquatica), we calculate the tertiary amine percentage (TA%=the tertiary amine concentration/(tertiary amine concentration+the corresponding N-oxide concentration) × 100). We found that the TA% for various PAs was genotype-dependent. Furthermore, TA% for the different PAs were correlated and the highest correlations occurred between PAs which share high structural similarity.
Resident-to-resident bedside teaching: An innovative concept.
Adhesion and the cell cycle in cultured L929 and CHO cells.
Author: Cross SJ, ap Gwynn I.
Abstract: The adhesiveness of L929 and CHO-K1 cells was monitored throughout their respective cell cycles. The cell cycle stages were identified by a combination of measuring, histochemical and autoradiographic techniques. Adhesiveness was shown to be maximal during the S and late G2 phases, and minimal at mitosis. S cells adhered selectively to other S cells, while late G2 phase cells adhered selectively to other late G2 cells. Mixing of the two cell lines, L929 and CHO-K1, resulted in the S phase cells adhering to each other irrespective of the cell line to which they belonged. The phases of increased adhesiveness and selectivity coincided with a decrease in cell surface negative charge, corresponding to well documented changes in the morphology of the cells.
Hydrolysis rates of pyrrolizidine alkaloids derived from Senecio jacobaea.
Author: Dueker SR, Lamé MW, Segall HJ.
Abstract: Many of the commonly studied pyrrolizidine alkaloids (PAs) are built upon the subgroup retronecine (RET), which is released from the parent molecule by either base catalyzed or enzymatic hydrolysis of the ester linkages. The rate of appearance of RET in a hydrolytic study would thus reflect the rate of hydrolysis for the PA being tested. We have developed a gas chromatographic (GC) method to measure the release of RET from incubations of PAs with the guinea pig carboxylesterase, GPH1. The PAs tested were the following: jacobine (JAB), jacozine (JAZ), retrorsine (RES), and seneciphylline (SNP). The KmS for SNP and JAZ were determined to be 64.9 and 349.2 microM, respectively. In addition, a qualitative assessment of hydrolytic activity toward a radiolabelled mixture of retrorsine/riddelliine (RES/RIL) was performed with HPLC and radiometric detection.
Vaccine discourse during the onset of the COVID-19 pandemic: Topical structure and source patterns informing efforts to combat vaccine hesitancy.
Author: Hwang J, Su MH, Jiang X, Lian R, Tveleneva A, Shah D.
Abstract: <h4>Background</h4>Understanding public discourse about a COVID-19 vaccine in the early phase of the COVID-19 pandemic may provide key insights concerning vaccine hesitancy. However, few studies have investigated the communicative patterns in which Twitter users participate discursively in vaccine discussions.<h4>Objectives</h4>This study aims to investigate 1) the major topics that emerged from public conversation on Twitter concerning vaccines for COVID-19, 2) the topics that were emphasized in tweets with either positive or negative sentiment toward a COVID-19 vaccine, and 3) the type of online accounts in which tweets with either positive or negative sentiment were more likely to circulate.<h4>Methods</h4>We randomly extracted a total of 349,979 COVID-19 vaccine-related tweets from the initial period of the pandemic. Out of 64,216 unique tweets, a total of 23,133 (36.03%) tweets were classified as positive and 14,051 (21.88%) as negative toward a COVID-19 vaccine. We conducted Structural Topic Modeling and Network Analysis to reveal the distinct topical structure and connection patterns that characterize positive and negative discourse toward a COVID-19 vaccine.<h4>Results</h4>Our STM analysis revealed the most prominent topic emerged on Twitter of a COVID-19 vaccine was "other infectious diseases", followed by "vaccine safety concerns", and "conspiracy theory." While the positive discourse demonstrated a broad range of topics such as "vaccine development", "vaccine effectiveness", and "safety test", negative discourse was more narrowly focused on topics such as "conspiracy theory" and "safety concerns." Beyond topical differences, positive discourse was more likely to interact with verified sources such as scientists/medical sources and the media/journalists, whereas negative discourse tended to interact with politicians and online influencers.<h4>Conclusions</h4>Positive and negative discourse was not only structured around distinct topics but also circulated within different networks. Public health communicators need to address specific topics of public concern in varying information hubs based on audience segmentation, potentially increasing COVID-19 vaccine uptake.
Pyrrolizidine alkaloids in arctiid moths (Lep.) with a discussion on host plant relationships and the role of these secondary plant substances in the Arctiidae
Author: Rothschild M, APLIN RT, COCKRUM PA, EDGAR JA, Fairweather P, Lees R.
Abstract: Pyrrolizidine alkaloids (PA) have been identified in six species of Arctiidae reared on Senecio and Crotalaria. These include senecionine, seneciphylline, integerrimine, jacobine, jacozine, jacoline, jaconine and a metabolite (C₁₅H₂₅NO₅) from Senecio, and monocrotaline, trichodesmine and crispatine from Crotalaria. The all-red aberration of Tyria jacobaeae (var. conyi) contained much less of the metabolite than normal examples of this species. Female Spilosoma lutea reared on the same plants of S. jacobaea contained markedly more jacobine and jacoline than die males. Host plant relationships and secondary plant substances are discussed. It is suggested that the Arctiid moths' own deterrent secretions, directed against vertebrate predators, pre-adapts them for feeding on foliage likewise protected against large herbivores by toxic secondary plant substances such as cardenolides and pyrrolizidine alkaloids. These latter substances are more toxic to vertebrate than to insect herbivores, and their dual function of deterrent and insect aphrodisiac puts a premium on their sequestration and storage once a species has achieved the initial steps, and occupied the plant niche concerned. It is further suggested that the polyphagous habits of the Arctiidae result in a more equitable distribution of die secondary plant substances within the Mullerian complex concerned, thus providing a generalized warning message for the potential vertebrate predator.