TXNIP May Play Role in Insulin Sensitivity in Caloric Restriction
Caloric restriction may improve insulin sensitivity via TXNIP.
(HealthDay News) — Caloric restriction improves peripheral insulin sensitivity, possibly by lowering insulin-stimulated thioredoxin-interacting protein (TXNIP) levels and enhancing non-oxidative glucose disposal, according to a study published in Diabetes.
Matthew L. Johnson, PhD, from Mayo Clinic College of Medicine in Rochester, Minnesota, and colleagues examined the underlying mechanism whereby caloric restriction improves insulin sensitivity in obese individuals.
In 11 obese participants, the authors examined the effect of 16 weeks of caloric restriction on whole-body insulin sensitivity by pancreatic clamp before and after caloric restriction compared with a matched control period (nine participants).
Data showed that caloric restriction increased the glucose infusion rate needed to maintain euglycemia during hyperinsulinemia, compared with control, indicating enhancement of peripheral insulin sensitivity.
Improved insulin sensitivity was not associated with changes in skeletal muscle mitochondrial oxidative capacity or oxidant emissions, nor with changes in skeletal muscle ceramide, diacylglycerol or amino acid metabolite levels.
Lower insulin-stimulated TXNIP levels and enhanced nonoxidative glucose disposal were seen with caloric restriction.
"These results support a role for TXNIP in mediating the improvement in peripheral insulin sensitivity after [caloric restriction]," the researchers wrote.