title: Intestinal Lymphatic Transport: an Overlooked Pathway for Understanding Absorption of Plant Secondary Compounds in Vertebrate Herbivores.
abstract: Herbivores employ numerous strategies to reduce their exposure to toxic plant secondary chemicals (PSCs). However, the physiological mechanisms of PSC absorption have not been extensively explored. In particular, the absorption of PSCs via intestinal lymphatic absorption has been largely overlooked in herbivores, even though this pathway is well recognized for pharmaceutical uptake. Here, we investigated for the first time whether PSCs might be absorbed by lymphatic transport. We fed woodrats (Neotoma albigula) diets with increasing concentrations of terpene-rich juniper (Juniperus monosperma) either with or without a compound that blocks intestinal lymphatic absorption (Pluronic L-81). Woodrats consuming diets that contained the intestinal lymphatic absorption blocker exhibited increased food intakes and maintained higher body masses on juniper diets. Our study represents the first demonstration that PSCs may be absorbed by intestinal lymphatic absorption. This absorption pathway has numerous implications for the metabolism and distribution of PSCs in the systemic circulation, given that compounds absorbed via lymphatic transport bypass first-pass hepatic metabolism. The area of lymphatic transport of PSCs represents an understudied physiological pathway in plant-herbivore interactions.
authors.affiliation: Department of Biological Sciences, Vanderbilt University, 465 21st Ave South, Nashville, TN, 37235, USA. kevin.d.kohl@gmail.com.|Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA. kevin.d.kohl@gmail.com.
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Kohl
authors.affiliation: Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA.
authors.forename: M Denise
authors.initials: MD
authors.lastname: Dearing
mesh_terms: D000818:Animals; D001692:Biological Transport; D060434:Herbivory; D007408:Intestinal Absorption; D018653:Juniperus / Q000378:metabolism*; D008208:Lymphatic System / Q000378:metabolism*; D016205:Sigmodontinae / Q000378:metabolism*
keywords: Herbivory; Lymphatic absorption; Plant secondary metabolites; Plant-herbivore interactions