"Chaotic Arrhythmia" During Successful Resuscitation After Ingestion of Yew (Taxus baccata) Needles

Venoarterial extracorporeal membrane oxygenation in combination with Levosimendan as a bridge to recovery for a case of severe yew intoxication in a 13-year-old patient

In an adolescent patient with severe yew intoxication and consecutive cardiac arrest, non-responsive to conventional resuscitation necessitating extracorporeal life support, Levosimendan has been implemented in the early acute phase of hemodynamic stabilization, without obvious side effects. However, the additive value of this treatment in severe yew intoxication remains speculative.

Inhibition of Tumor Growth and Modulation of Antioxidant Activity of Rhodoxanthin Isolated from Taxus baccata Aril against B16F10 Murine Malignant Melanoma

Malignant melanoma is the most aggressive type of skin cancer, and due to the numerous limitations of current treatment methods, there is an urgent need to develop novel approaches for both the prevention and treatment of malignant melanoma, with research-oriented bioactive substances representing a notable first step. The current study decided to expand on previous rhodoxanthin research by investigating the possible anti-tumor effect as well as the effect on the antioxidant status in the case of murine melanoma in an experimental model. The 21-day study was carried out on female C57BL/6J mice. On the first day of the experiment, they were subcutaneously inoculated with 106 B16F10 cells and were given rhodoxanthin orally until the end of the study. Rhodoxanthin supplementation significantly reduced tumor growth (42.18%) and weight (15.74%). Furthermore, the epidermal growth factor (EGF) activity was reduced and the concentration of 8-OHdG dropped in the treated melanoma-bearing mice compared to the untreated ones, demonstrating the role of rhodoxanthin in slowing tumor growth, one of the mechanisms being the reduction of EGF level and the decrease of DNA oxidation. The administration of rhodoxanthin determined variations in antioxidant enzymes, both at the plasma level and at the tissue level.

Phytochemical Characterization of Taxus baccata L. Aril with Emphasis on Evaluation of the Antiproliferative and Pro-Apoptotic Activity of Rhodoxanthin

Taxus baccata L., an evergreen tree, was known until recently due to its high concentration of toxic compounds. The purpose of the present study was to focus on the only non-poisonous part, the red arils, which have recently been described as an important source of various bioactive constituents. To establish total phenolic, flavonoid, and carotenoid content, antioxidant capacity, and cytotoxic properties, two types of extracts were obtained. The chemical profile of the ethanolic extract was evaluated using chromatographic (HPLC-DAD-ESI+) and spectral (UV-Vis) methods, and the antioxidant activity of the ethanolic extract was assessed using DPPH and FRAP assays, yielding moderate results. In the second type of extract (methanol: ethyl acetate: petroleum ether (1:1:1, v/v/v)) we identified three carotenoids using open column chromatography and RP–PAD–HPLC, with rhodoxanthin being the most abundant. Considering the above and mainly because of the lack of information in the literature about this pigment and its biological effects, we decided to further investigate the cytotoxic activity of rhodoxanthin, the main carotenoid presented in aril, and its protective effect against H₂O₂-induced oxidative stress using two cell lines: human HaCaT keratinocytes and B16F10 murine malignant melanoma. The MTT and Annexin-V Apoptosis assays showed a substantial cytotoxic potential expressed in a dose-dependent manner towards the melanoma cell line, however, no obvious cytotoxic effects on human keratinocytes were noticed.

Fatal heart block from intentional yew tree (Taxus baccata) ingestion: a case report

BACKGROUND

Taxus baccata, also known as English yew, is a poison that causes cardiac arrhythmias and can result in death from cardiogenic shock.

CASE SUMMARY

A 49-year-old gentleman was admitted following yew ingestion with suicidal intent. He was bradycardic at 30 b.p.m. and hypotensive on arrival. Electrocardiography revealed complete heart block with broad complex ventricular escape rate of 30 b.p.m. Bedside echocardiography revealed severe global impairment of right and left ventricular systolic function. Urgent temporary transvenous pacing was instituted, and the patient was considered for veno-arterial extracorporeal membrane oxygenation. Unfortunately, he deteriorated rapidly and cardiorespiratory arrest ensued, and despite prolonged in-hospital resuscitation, the patient died. Post-mortem examination revealed small needle-shaped plant leaves together with seeds found in the stomach. Ante mortem serum sample analysis sent to the Royal Botanical Gardens and revealed the presence of taxine Type B alkaloids in the patient's blood.

DISCUSSION

Yew poisoning is a rare occurrence, and there is currently no effective antidote. Treatment involves supportive management, comprising prolonged effective cardiopulmonary resuscitation, pacing, and mechanical cardiac support. This case illustrates the importance of prompt recognition of yew poisoning, alongside early consideration of pacing and mechanical cardiac support. Due to the rarity of this cause of heart block, and since patients may not always volunteer a history of yew ingestion, yew poisoning is something that physicians should be aware of and this should be considered in the differential diagnosis in patients with unexpected heart block. Serum analysis for taxine alkaloids can be used to confirm the diagnosis.

Clinical Toxicology of Yew Poisoning

Objectives: Yew plant materials contain highly toxic taxine alkaloids. Serious ingestions can result in life-threatening toxicity. The purpose of this article is to summarize the literature on the treatment of acute yew poisoning. Data Sources: PubMed (January 1946 to November 2017) was searched using the search terms “taxus/po”. EMBASE (1980 to November 2017) was searched using the search terms “taxus/to” and “yew.mp.” Web of Science (1945 to November 2017) was searched using the text words taxus, taxine, and yew. Study Selection and Data Extraction: Available English language articles involving case reports, epidemiology, treatment, and outcomes were included. Data Synthesis: Although not uncommon, unintentional yew poisoning rarely results in significant morbidity or mortality. A total of 26 case reports of yew poisoning were evaluated along with 4 case series articles (totaling 22 additional cases). Only 4 of the 48 total cases (8%) were accidental poisonings, the rest being deliberate ingestions. In 20 patients (42%), it resulted in fatalities. Severe, acute yew poisoning results in symptomatology largely resistant to pharmacotherapy intervention. Conclusions: Most nonintentional ingestions of yew plant constituents are asymptomatic and require little intervention. Severe poisoning can result in life-threatening cardiac toxicity and require aggressive supportive care. Therapeutic interventions, such as sodium bicarbonate, digoxin immune fab, and hemodialysis that have been utilized in case studies and case series in the literature have little proven benefit. Extracorporeal life support should be considered in severe yew poisoning.