Investigation of cardiac glycosides from oleander in a human induced pluripotent stem cells derived cardiomyocyte model.

The ingestion of Nerium oleander and Thevetia peruviana are common causes for poisoning in Southeast Asia. All parts of the oleander shrub contain cardiac glycosides of the cardenolide type. These glycosides act via inhibition of a Na+/K+-ATPase which might cause severe arrhythmia and subsequent death in oleander-poisoned patients. The current study uses human induced pluripotent stem cells derived cardiomyocytes (hiPSC-CM) in a microelectrode array (MEA) system to assess the cardiac effects of neriifolin, oleandrin, digitoxigenin, peruvoside and thevetin A from the oleander plant. Digoxin was used as established reference compound. All tested compounds showed a corrected field potential duration (FPDc) shortening and was the lowest for 600 nM digitoxigenin with -36.9 ± 1.2 %. Next to the dose-dependent pro-arrhythmic potential, a complete beat arrest of the spontaneously beating hiPSC-CM was observed at a concentration of 300 nM for neriifolin, 600 nM for oleandrin and 1000 nM for digitoxigenin and peruvoside. Thevetin A did not cause arrhythmia up to a final concentration of 1000 nM. Thus, it was possible to establish a cardiac effect rank order of the tested substances: neriifolin > oleandrin > digitoxigenin = peruvoside > digoxin > thevetin A.

Death from cardiac glycoside "pong-pong" following use as weight-loss supplement purchased on Internet.

Cerbera odollam or "pong-pong" tree contains cardiac glycosides similar to digoxin, oleander and yellow oleander. Cerbera odollam is a common method of suicide in South East Asia and has also been used as a weight loss supplement. We present a case of a 33-year-old female presenting with lethargy, vomiting, bradycardia, severe hyperkalemia of 8.9 mEq/L, slow atrial fibrillation followed by cardiovascular collapse following the ingestion of "pong-pong", the kernel of Cerbera odollam, as a weight loss supplement. Despite the administration of a total of nine vials of digoxin-specific Fab the patient could not be resuscitated. Clinicians should be aware of natural cardiac glycosides being uses as weight-loss agents and consider acute cardiac glycoside poisoning in patients with hyperkalemia, abnormal cardiovascular signs, symptoms and abnormal ECG findings.

Identification and screening of cardiac glycosides in Streptocaulon griffithii using an integrated data mining strategy based on high resolution mass spectrometry.

The present study was designed to develop a practical strategy to tackle the problem of lacking standard compounds and limited references for identifying structure-related compounds in Streptocaulon griffithii Hook. f., especially those in trace concentrations, with a focus on antitumor activity. The cardiac glycosides (CGs)-enriched part was determined using in vitro bioactive assays in three cancer cell lines and then isolated using macroporous resins. The MS and MS/MS data were acquired using a high performance liquid chromatography coupled with hybrid quadrupole-time of flight (HPLC-Q-TOF-MS) system. To acquire data of trace compound in the extract, a multiple segment program was applied to modify the HPLC-Q-TOF-MS method. A mass defect filter (MDF) approach was employed to make a primary MS data filtration. Utilizing a MATLAB program, the redundant peaks obtained by imprecise MDF template calculated with limited references were excluded by fragment ion classification, which was based on the ion occurrence number in the MDF-filtered total ion chromatograms (TIC). Additionally, the complete cleavage pathways of CG aglycones were proposed to assist the structural identification of 29 common fragment ions (CFIs, ion occurrence number ≥ 5) and diagnostic fragment ions (DFIs, ion occurrence number < 5). As a result, 30 CGs were filtered out from the MDF results, among which 23 were identified. This newly developed strategy may provide a rapid and effective tool for identifying structure-related compounds in herbal medicines.

Toxicity of the spiny thick-foot Pachypodium.

PREMISE OF THE STUDY: Pachypodium (Apocynaceae) is a genus of iconic stem-succulent and poisonous plants endemic to Madagascar and southern Africa. We tested hypotheses about the mode of action and macroevolution of toxicity in this group. We further hypothesized that while monarch butterflies are highly resistant to cardenolide toxins (a type of cardiac glycoside) from American Asclepias, they may be negatively affected by Pachypodium defenses, which evolved independently. METHODS: We grew 16 of 21 known Pachypodium spp. and quantified putative cardenolides by HPLC and also by inhibition of animal Na+ /K+ -ATPase (the physiological target of cardiac glycosides) using an in vitro assay. Pachypodium extracts were tested against monarch caterpillars in a feeding bioassay. We also tested four Asclepias spp. and five Pachypodium spp. extracts, contrasting inhibition of the cardenolide-sensitive porcine Na+ /K+ -ATPase to the monarch's resistant form. KEY RESULTS: We found evidence for low cardenolides by HPLC, but substantial toxicity when extracts were assayed on Na+ /K+ -ATPases. Toxicity showed phylogenetic signal, and taller species showed greater toxicity (this was marginal after phylogenetic correction). Application of Pachypodium extracts to milkweed leaves reduced monarch growth, and this was predicted by inhibition of the sensitive Na+ /K+ -ATPase in phylogenetic analyses. Asclepias extracts were 100-fold less potent against the monarch compared to the porcine Na+ /K+ -ATPase, but this difference was absent for Pachypodium extracts. CONCLUSIONS: Pachypodium contains potent toxicity capable of inhibiting sensitive and cardenolide-adapted Na+ /K+ -ATPases. Given the monarch's sensitivity to Pachypodium, we suggest that these plants contain novel cardiac glycosides or other compounds that facilitate toxicity by binding to Na+ /K+ -ATPases.

Toxic levels of glycosides in herbal medication: a potential cause of hyperkalaemia.

We report a previously healthy man presenting with life-threatening hyperkalaemia and heart failure. The only possible cause was thought to be the long list of herbal medications he was taking, several of which contained significant amounts of cardiac glycosides. Hyperkalaemia is known to be associated with digoxin toxicity and we present this as the likely cause in this case, and emphasize the importance of a thorough drug history in forming a differential diagnosis.

Molluscicidal activity of cardiac glycosides from Nerium indicum against Pomacea canaliculata and its implications for the mechanisms of toxicity.

Cardiac glycosides from fresh leaves of Nerium indicum were evaluated for its molluscicidal activity against Pomacea canaliculata (golden apple snail: GAS) under laboratory conditions. The results showed that LC(50) value of cardiac glycosides against GAS was time dependent and the LC(50) value at 96 h was as low as 3.71 mg/L, which was comparable with that of metaldehyde at 72 h (3.88 mg/L). These results indicate that cardiac glycosides could be an effective molluscicide against GAS. The toxicological mechanism of cardiac glucosides on GAS was also evaluated through changes of selected biochemical parameters, including cholinesterase (ChE) and esterase (EST) activities, glycogen and protein contents in hepatopancreas tissues of GAS. Exposure to sublethal concentrations of cardiac glycosides, GAS showed lower activities of EST isozyme in the later stages of the exposure period as well as drastically decreased glycogen content, although total protein content was not affected at the end of 24 and 48 h followed by a significant depletion at the end of 72 and 96 h. The initial increase followed by a decline of ChE activity was also observed during the experiment. These results suggest that cardiac glycosides seriously impair normal physiological metabolism, resulting in fatal alterations in major biochemical constituents of hepatopancreas tissues of P. canaliculata.

Toxic and sub-lethal effects of oleandrin on biochemical parameters of fresh water air breathing murrel, Channa punctatus (Bloch.).

Active compound oleandrin extracted from Nerium indicum (Lal Kaner) leaf has potent piscicidal activity. The piscicidal activity of oleandrin on freshwater fish C. punctatus was both time and dose dependent. Exposure to sub-lethal doses of oleandrin for 24hr and 96hr to fish caused significant alteration in the level of total protein, total free amino acid, nucleic acid, glycogen, pyruvate, lactate and enzyme protease, phosphatases, alanine aminotransferase, aspartate aminotransferase and acetylcholinesterase activity in liver and muscle tissues. The alterations in all the above biochemical parameters were also significantly time and dose dependent. The results show a significant recovery in all the above biochemical parameters, in both liver and muscle tissues of fish after the 7th day of the withdrawal of treatment. Toxicity persistence test of oleandrin on juvenile Labeo rohita shows that fish seed of common culturing carp can be released into rearing ponds after three days of oleandrin treatment. It supports the view that the oleandrin is safer and may be useful substitute of other piscicides for removing the unwanted freshwater fishes from aquaculture ponds.

Oleander toxicity: an examination of human and animal toxic exposures.

The oleander is an attractive and hardy shrub that thrives in tropical and subtropical regions. The common pink oleander, Nerium oleander, and the yellow oleander, Thevetia peruviana, are the principle oleander representatives of the family Apocynaceae. Oleanders contain within their tissues cardenolides that are capable of exerting positive inotropic effects on the hearts of animals and humans. The cardiotonic properties of oleanders have been exploited therapeutically and as an instrument of suicide since antiquity. The basis for the physiological action of the oleander cardenolides is similar to that of the classic digitalis glycosides, i.e. inhibition of plasmalemma Na+,K+ ATPase. Differences in toxicity and extracardiac effects exist between the oleander and digitalis cardenolides, however. Toxic exposures of humans and wildlife to oleander cardenolides occur with regularity throughout geographic regions where these plants grow. The human mortality associated with oleander ingestion is generally very low, even in cases of intentional consumption (suicide attempts). Experimental animal models have been successfully utilized to evaluate various treatment protocols designed to manage toxic oleander exposures. The data reviewed here indicate that small children and domestic livestock are at increased risk of oleander poisoning. Both experimental and established therapeutic measures involved in detoxification are discussed.

[Phytotherapeutic aspects of diseases of the circulatory system. III. Cardiotonic and cardiotoxic effects of hyrcanoside and deglucohyrcanoside isolated from Coronilla varia L]. / Fytoterapeutické aspekty onemocnení obehového systému. III. Kardiotonický a kardiotoxický úcinek hyrkanosidu a deglukohyrkanosidu izolovaných z Coronilla varia L.

The Cardiotonic and cardiotoxic effects of two cardiac glycosides-hyrcanoside and deglucohyrcanoside-isolated from the seeds of Coronilla varia L. were evaluated in the paper--in comparison with the effect and toxicity of digoxin and ouabain. Evaluation of the cardiotonic effect using the methods of heart "in situ" and the isolated heart (Langendorff) proved that deglucohyrcanoside is more effective than hyrcanoside and that its effect is equal to that of digoxin as well as ouabain. The efficacy of deglucohyrcanoside et least to that of digoxin, while the toxicity of the former is several times lower, makes the glycoside a potential candidate for therapeutic use.

The Moraceae-based dart poisons of South America. Cardiac glycosides of Maquira and Naucleopsis species.

The use of cardenolide-containing Moraceae in the dart poisons of South America is reviewed. Those prepared by the Chocó Indians of western Colombia--called niaará or kieratchi--have probably been made from the latex of Naucleopsis amara and N. glabra. In Ecuador, the Colorado Indians used N. chiguila, while the Coaiquer Indians still derive a poison from the latex of N. naga and the Cayapá Indians occasionally make use of a blowgun poison, hambi, which probably also comes from a Naucleopsis species. The Kaborí (Rio Uneiuxi Makú) Indians of north-western Brazil may have utilized Maquira coriacea, but a more recent collection documents N. mello-barretoi latex as a source of their poison. The Tikuna Indians of western Brazil included leaves and bark of N. stipularis in one of their poisons. The principal cardiac glycosides present in Maquira species are strophanthidin-based and the main ones occurring in Naucleopsis species are antiarigenin- as well as strophanthidin-based. The structures of two new glycosides, isolated from dart-poison samples, have been established as strophanthidin beta-D-glucomethylosido-D-alloside and beta-D-digitoxosido-D-alloside. The former is a major component of pakurin, the crystalline glycoside mixture prepared by Santesson in 1928 from a Chocó Indian poison.

Digoxin-specific Fab fragments in the treatment of oleander toxicity in a canine model.

STUDY OBJECTIVE: To examine the efficacy of digoxin-specific Fab fragments (dsFab) in the treatment of experimentally induced Nerium oleander cardiac glycoside toxicity in a dog model. DESIGN: A nonblined, placebo-controlled experiment. SUBJECTS: Ten adult greyhound dogs of either sex divided into treatment and control groups of five dogs each. INTERVENTIONS: A tincture of oleander was prepared and administered intravenously to each animal. After the onset of cardiotoxicity, the treatment group received 60 mg/kg dsFab IV. MEASUREMENTS AND MAIN RESULTS: All dogs exhibited dysrhythmias meeting our criteria for cardiac glycoside cardiotoxicity within 27 minutes of beginning the infusion. Three of five control dogs had lethal dysrhythmias during the three-hour observation period. The remaining two control dogs exhibited dysrhythmias throughout the three-hour experiment. All five of the dsFab-treated dogs survived and converted to normal sinus rhythm within eight minutes of dsFab infusion. Three treatment animals reverted back to nonlethal and hemodynamically stable dysrhythmias after a mean of 107 minutes. CONCLUSION: Large doses of dsFab are efficacious in the treatment of dysrhythmias in this canine model of N oleander cardiac glycoside poisoning.

Cellular basis for the species differences in sensitivity to cardiac glycosides (digitalis).

The relative toxicity of numerous cardiotonic steroids (viz. ouabain, digitoxin, digoxin, convallatoxin, SC4453, bufalin, gitaloxin, digoxigenin, actodigin, oleandrin, digitoxigenin, gitoxin, strophanthidin, gitoxigenin, lanatosides A, B and C, alpha- and beta-acetyl digoxin, alpha- and beta-methyl digoxin) and related compounds towards a number of independent cell lines established from human, monkey, mouse, Syrian hamster, and Chinese hamster have been determined. All cardiac glycosides and their genins, as well as the cardiotonic alkaloid cassaine, exhibited greater than 100-fold higher toxicity towards cultured human and monkey cells in comparison to the cell lines of mouse, Syrian hamster, and Chinese hamster origins. These differences are species-related as all cell lines (both normal as well as transformed) from any one species, as well as cells from the closely related species (e.g., man and monkey or mouse, Chinese hamster, and Syrian hamster), showed similar sensitivity towards these drugs. The failure to see any significant differences in cellular toxicity for a larger number of other compounds which either bear limited structural resemblance to cardiac glycosides (viz. estradiol 17-beta-acetate, testosterone propionate, 21-acetoxy pregnenolone, beta-estradiol, digitonin, tigogenin, and tomatine) or interact with the Na+/K+ ATPase in a different manner (viz. veratridine, sanguinarine nitrate, penicillic acid, vanadium pentoxide, harmaline-HCI,5,5'-diphenyl hydantoin, quindonium bromide, and methyl quinolizinum bromide) provides strong evidence that the observed species-related differences are highly specific for cardiotonic steroids. Studies on the binding of [3H]ouabain show that, in comparison to human and monkey cell lines, no significant binding of the drug is observed in cells derived from the resistant species (i.e., mouse and Chinese hamster). The Na+/K+ ATPase from cells of the resistant species is inhibited at much higher concentrations of ouabain and digitoxin in comparison to the enzyme from human cells, and a good correlation is observed between these concentrations and those reported for inhibition of the enzyme from isolated heart muscles of the same species. These results provide strong evidence that the species-related differences in sensitivity to digitalis have a cellular basis and that the cultured cells from various mammalian species provide a useful model system for investigating the mechanism of action of cardiac glycosides.

Toxicological study of the different organs of Corchorus olitorius L. plant with special reference to their cardiac glycosides content.

The acute toxicity of the alcoholic extracts of seeds, roots stems and leaves of the fully mature Corchorus olitorius L. plant was determined in mice by intraperitoneal injection. The cardiac glycosides content of each extract was estimated and the correlation between the two investigated parameters was established. The chronic toxicity of the alcoholic extract of the seeds was determined in term of its haematological and symptomatical effects on mice upon intraperitoneal injection for a period of two months.