Skip to content
Search Library
thumbnail

The hormones insulin and leptin are responsible for energy balance. Their regulation is often disturbed in horses that suffer from insulin resistance and equine metabolic syndrome, which predisposes them to more devastating metabolic problems such as laminitis. Lipoic acid has improved glucose utilization and insulin activity in humans and certain animals. Researchers recently presented results of a study that examined glucose and insulin dynamics as well as leptin serum concentrations in pony mares supplemented with lipoic acid.

Eleven pony mares of similar body condition between the ages of 8 and 18 were supplemented with either 10 mg/kg body weight of lipoic acid in maple syrup once a day for 14 days or were used as controls. The mares were individually fed 2% of their body weight of mixed grass hay, and the average body condition score (BCS) for both groups was approximately 7 (on a BCS scale of 1-9). An intravenous glucose tolerance test (IVGTT) was performed on day 14 of the study to determine glucose and insulin dynamics. This was done by collecting a baseline sample one hour prior and immediately before dosing with glucose. Twenty minutes later an intravenous dose of insulin was given and blood samples collected at predetermined intervals from 3 to 180 minutes post-dosing.

Samples were analyzed for glucose, insulin, and leptin. Areas under the curve for glucose, insulin, and leptin were calculated for comparison of treated horses to the controls.

Lipoic acid supplementation appeared to have an effect of reducing insulin response, as noted by a greater area under the curve for insulin in the control ponies than in the ponies supplemented with lipoic acid. There were no differences in glucose or leptin responses between treated and control ponies. The action of lipoic acid may have been to enhance the glucose clearing capacity of insulin, thus less insulin was needed to clear the same amount of glucose from the bloodstream. This preliminary study merits further research on the ability of supplementation with lipoic acid to enhance insulin effectiveness in horses with compromised metabolic status.

This study was presented at the 2011 Equine Science Society Symposium in Murfreesboro, Tenn. The proceedings from this symposium are available from the Journal of Equine Veterinary Science.

X

Subscribe to Equinews and get the latest equine nutrition and health news delivered to your inbox. Sign up for free now!