"Pharm-ecology" of diet shifting: biotransformation of plant secondary compounds in creosote (Larrea tridentata) by a woodrat herbivore, Neotoma lepida.
Physiol Biochem Zool
; 81(5): 584-93, 2008.
Article
en En
| MEDLINE
| ID: mdl-18752424
ABSTRACT
Diet switching in mammalian herbivores may necessitate a change in the biotransformation enzymes used to process plant secondary compounds (PSCs). We investigated differences in the biotransformation system in the mammalian herbivore, Neotoma lepida, after a radical shift in diet and secondary compound composition. Populations of N. lepida in the Mojave Desert have evolved over the past 10,000 years to feed on creosote (Larrea tridentata) from an ancestral state of consuming juniper (Juniperus osteosperma). This dietary shift represents a marked change in the dietary composition of PSCs in that creosote leaves are coated with phenolic resin, whereas juniper is high in terpenes but lacks phenolic resin. We quantified the enzyme activity of five major groups of biotransformation enzymes (cytochrome P450s, NAD(P)Hquinone oxidoreductase, glutathione conjugation, sulfation, and glucuronidation) recognized for their importance to mammalian biotransformation for the elimination of foreign compounds. Enzyme activities were compared between populations of Mojave and Great Basin woodrats fed control and creosote diets. In response to creosote, the Mojave population had greater levels of cytochrome P450s (CYP2B, CYP1A) and glutathione conjugation liver enzymes compared with the Great Basin population. Our results suggest that elevated levels of cytochrome P450s and glutathione conjugation enzymes in the Mojave population may be the underlying biotransformation mechanisms that facilitate feeding on creosote.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Roedores
/
Adaptación Biológica
/
Larrea
/
Dieta
/
Enzimas
Límite:
Animals
País/Región como asunto:
America do norte
Idioma:
En
Revista:
Physiol Biochem Zool
Asunto de la revista:
BIOLOGIA
/
FISIOLOGIA
Año:
2008
Tipo del documento:
Article
País de afiliación:
Estados Unidos