Stegelmeier Bryan L, Davis T Zane
USDA/ARS Poisonous Plant Research Laboratory, 1150 East 1400 North, Logan, UT 84341, USA.
USDA/ARS Poisonous Plant Research Laboratory, 1150 East 1400 North, Logan, UT 84341, USA.
Toxicon. 2023 Oct;234:107286. doi: 10.1016/j.toxicon.2023.107286. Epub 2023 Sep 10.
Rayless goldenrod (Isocoma spp.) and white snakeroot (Ageratina altissima) poison livestock, wildlife and humans. The suggested toxin for both plants is tremetone, a mixture of benzofuran ketones. However, plant tremetone concentrations often do not correlate with poisoning, and they have not been identified in contaminated milk that poisons nursing neonates. This suggests there may be unidentified metabolites or toxins. Previous studies using various cell culture and large animal models have been inconsistent with varying animal response that often require large doses. The objective of this work is to document the toxicity of rayless goldenrod in California white leghorn chicks, a susceptible small animal model, that would require relatively small amounts of plant material or purified toxins. Four groups of 15 chicks were gavaged with finely ground I. pluriflora at rates of 0, 1%, 2% or 3% of their bodyweight per day for 7 days. After 7 exposure days the chicks were euthanized, necropsied and tissues were collected, fixed and examined microscopically. Myocyte damage was evaluated using clinical signs, weight gain, serum biochemical changes, and histologic lesions and scores. The 3% group had focally extensive myocyte degeneration and necrosis most severely affecting leg muscles (semitendinosus, iliotibialis, peroneus longus and gastrocnemius). This was supported by serum biochemical changes and reduced weight gains. These findings indicate young chicks are a sensitive model of toxicity that may be useful to better identify the rayless goldenrod and white snakeroot toxins, including those unidentified toxins of transmammary poisoning.
无叶金光菊（异苞菊属）和白蛇根草（藿香蓟）会毒害家畜、野生动物和人类。这两种植物的疑似毒素是震颤酮，一种苯并呋喃酮混合物。然而，植物中的震颤酮浓度往往与中毒情况不相关，而且在毒害哺乳新生儿的受污染牛奶中也未检测到。这表明可能存在未被识别的代谢物或毒素。以往使用各种细胞培养和大型动物模型的研究结果并不一致，动物反应各异，且往往需要大剂量。这项工作的目的是记录无叶金光菊对加利福尼亚白来航鸡的毒性，白来航鸡是一种易感的小型动物模型，所需植物材料或纯化毒素的量相对较少。将四组每组15只雏鸡每天按其体重的0%、1%、2%或3%灌喂磨碎的多花异苞菊，持续7天。暴露7天后，对雏鸡实施安乐死、进行尸检并收集组织，固定后进行显微镜检查。使用临床症状、体重增加、血清生化变化以及组织学损伤和评分来评估心肌细胞损伤。3%组出现局灶性广泛的心肌细胞变性和坏死，对腿部肌肉（半腱肌、髂胫肌、腓骨长肌和腓肠肌）影响最为严重。血清生化变化和体重增加减少也证实了这一点。这些发现表明幼雏是一种敏感的毒性模型，可能有助于更好地识别无叶金光菊和白蛇根草毒素，包括那些经乳腺中毒的未识别毒素。
