Decreased adiponectin concentrations are linked with the laminitis prone phenotype in equids with insulin dysregulation and equine metabolic syndrome (EMS). The high molecular weight (HMW) form of adiponectin is closely linked with insulin sensitivity, and thiazolidinedione drugs increase total and HMW adiponectin concentrations and improve insulin sensitivity in humans. The thiazolidinedione drug pioglitazone is orally absorbed in the horse and is safe and affordable for long-term management. The hypothesis was that pioglitazone would decrease insulin response to oral sugar and increase HMW adiponectin concentrations in horses and ponies.
Two cohorts of healthy equids, 7 horses (mean Henneke body condition score [BCS] 6.8 of 9) and 8 ponies (mean BCS 6.1 of 9), were treated with pioglitazone (2 mg/kg per os q24 h) for 28 days. Serum HMW adiponectin concentrations were measured by ELISA at 0, 14, and 28 days after treatment. Oral sugar tests (OST) were performed at days 0 and 28. A two-way repeated measures ANOVA with Sidak’s multiple comparisons test was used for data analysis. Cohorts compared were the ponies, horses, and insulin dysregulated (ID) equids (defined as horses or ponies having insulin concentrations > 65 µU/ml during the OST at ≥ 60 minutes).
Insulin concentrations were significantly lower after pioglitazone at the 90 and 120 minute time points of the OST in ponies [P = 0.0035] and ID equids [P = 0.0028], but not the horses [P = 0.4970]. HMW adiponectin was significantly higher after treatment in horses [P < 0.01, baseline 2.5 ± 1.0 µg/ml; endpoint 4.9 ± 2.9 µg/ml], ponies [P < 0.05, baseline 1.6 ± 2.6 µg/ml; endpoint 3.3 ± 4.4 µg/ml], and ID equids [P=0.0272, baseline 1.0 ± 8.0 µg/ml; endpoint 2.3 ± 1.8 µg/ml].
Lower insulin concentrations during the OST and increased HMW adiponectin concentrations indicate positive effects of pioglitazone for treatment of metabolic derangements in equids with EMS.
Equine Internal Medicine Resident
Department of Clinical Sciences, Auburn University College of Veterinary Medicine
Dr. Legere is currently an Equine Internal Medicine Resident at Auburn University College of Veterinary Medicine in Auburn, Alabama. She received her DVM from Kansas State University in 2015, followed by a rotating equine internship at Weatherford Equine Medical Center in Weatherford, Texas. Prior to veterinary school, she earned a BS in Biomedical Engineering from Worcester Polytechnic Institute, worked in research and development in the medical device industry, and then earned her MS in Equine Science from Sul Ross State University in Alpine, Texas.
Thursday, June 14
1:45 PM – 2:00 PM
The asset you are trying to access is locked. Please enter your access key to unlock.