Details

Autor(en) / Beteiligte

• Basile, Anthony J.
• Kreisler, Avin
• Hassen, Ryan
• Singh, Kavita
• Symes, Maggie
• Larson, Gale
• de Sousa, Milena Figueiredo
• Sweazea, Karen L.

Titel

Acute metformin induces hyperglycemia in healthy adult mourning doves, Zenaida macroura

Ist Teil von

• Comparative biochemistry and physiology. Part A, Molecular & integrative physiology, 2024-05, Vol.291, p.111594-111594, Article 111594

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2024

Link zum Volltext

Quelle

ScienceDirect

Beschreibungen/Notizen

• Birds have the highest blood glucose among vertebrates. Several mechanisms may explain this including the lack of a functional insulin-responsive glucose transport protein, high glucagon concentrations, and reliance on lipid oxidation resulting in the production of gluconeogenic precursors. The hypothesis was that interruption of gluconeogenesis using the diabetes medication metformin would lower glucose concentrations in wild-caught birds. We captured two cohorts of adult mourning doves, Zenaida macroura, and acclimated them to captivity for two weeks. In this crossover study, cohort 1 was administered a single dose of one of the following oral treatments each week: metformin (150 or 300 mg/kg), glycogenolysis inhibitor (2.5 mg/kg 1,4-dideoxy-1,4-imino-D-arabinitol (DAB)), or water (50 μL). Whole blood glucose was measured using a glucometer at baseline, 30, 60, and 120 min following the oral doses. In contrast to mammals and chickens, 300 mg/kg metformin did not alter blood glucose (p > 0.05) whereas 150 mg/kg metformin increased blood glucose compared to water (p = 0.043). To examine whether 150 mg/kg metformin stimulated glycogenolysis, we co-administered 150 mg/kg metformin and 2.5 mg/kg DAB, which prevented the hyperglycemic response. Cohort 2 was administered the same treatments and the early response was examined (0, 5, 10, 15 min). Low-dose metformin increased blood glucose within 5 min (p = 0.039) whereas the high dose had no effect. DAB did not prevent the early response to metformin nor did it alter blood glucose concentrations when administered alone (p = 0.887). In conclusion, metformin increases endogenous blood glucose via glycogenolysis in healthy adult male mourning doves. [Display omitted] •Birds have naturally high blood glucose concentrations.•Many species, such as mourning doves, typically oxidize fats for metabolism.•We hypothesized that gluconeogenesis may contribute to the high glucose.•In contrast to chickens, metformin increased glucose via glycogenolysis in doves.•These results are similar to findings in healthy humans.