Author
Stegelmeier, Bryan | |
Davis, Thomas - Zane | |
Welch, Kevin | |
Green, Benedict - Ben | |
Gardner, Dale | |
Lee, Stephen | |
Pfister, James | |
Cook, Daniel | |
Panter, Kip |
Submitted to: International Symposium on Poisonous Plants
Publication Type: Proceedings Publication Acceptance Date: 5/30/2015 Publication Date: 6/5/2015 Citation: Stegelmeier, B.L., Davis, T.Z., Welch, K.D., Green, B.T., Gardner, D.R., Lee, S.T., Pfister, J.A., Cook, D., Panter, K.E. 2015. Species susceptibility to locoweed poisoning and evaluation of chicks as a small animal model of poisoning. International Symposium on Poisonous Plants. 9:126-129. Interpretive Summary: Locoweed poisoning has largely been attributed to the effects of mannosidase inhibiting swainsonine. However, there are many plants that contain mixtures of swainsonine and other glycosidase inhibiting alkaloids such as calystegines, castanospermine, and other minor alkaloids or metabolites like lentiginosine. The toxic and physiologic effects of these alkaloids are poorly characterized as are the effects of combined intoxication as is frequently the case when plants contain swainsonine and calystegines. Testing and characterizing the effects of purified alkaloids has been difficult. The objectives of this study were to evaluate the use of birds as a model for locoweed poisoning by comparing the effects of locoweed poisoning in chicks with those we have previously documented in other species. Twenty-five, day old chicks were randomly divided into 5 groups of 5 birds. These groups were dosed twice a day via oral gavage with finely ground locoweed (Astragalus lentiginosus) to obtain doses of 0, 0.25, 0.75, 2.25 and 10 mg swainsonine/KG body weight/day for 30 days. We found that relatively high swainsonine doses did not produce significant clinical disease and minimal histologic changes. These findings suggest that chicks, and probably many birds, are resistant to locoweed poisoning and will not be a good model to study swainsonine or other glycosidase inhibiting alkaloids. Currently in vitro assays of serum and other tissues of swainsonine-inhibited mannosidases are being evaluated to easily screen additional species and more quickly identify an appropriate small animal model. Technical Abstract: Locoweed poisoning has largely been attributed to the effects of mannosidase inhibiting swainsonine. However, there are many plants that contain mixtures of swainsonine and other glycosidase inhibiting alkaloids such as calystegines, castanospermine, and other minor alkaloids or metabolites like lentiginosine. The toxic and physiologic effects of these alkaloids are poorly characterized as are the effects of combined intoxication as is frequently the case when plants contain swainsonine and calystegines. Testing and characterizing the effects of purified alkaloids has been difficult. The objectives of this study were to evaluate the use of birds as a model for locoweed poisoning by comparing the effects of locoweed poisoning in chicks with those we have previously documented in other species. Twenty-five, day old chicks were randomly divided into 5 groups of 5 birds. These groups were dosed twice a day via oral gavage with finely ground locoweed (Astragalus lentiginosus) to obtain doses of 0, 0.25, 0.75, 2.25 and 10 mg swainsonine/KG body weight/day for 30 days. We found that relatively high swainsonine doses did not produce significant clinical disease and minimal histologic changes. These findings suggest that chicks, and probably many birds, are resistant to locoweed poisoning and will not be a good model to study swainsonine or other glycosidase inhibiting alkaloids. Currently in vitro assays of serum and other tissues of swainsonine-inhibited mannosidases are being evaluated to easily screen additional species and more quickly identify an appropriate small animal model. |