TY - JOUR
T1 - Effects of long-term calorie restriction and endurance exercise on glucose tolerance, insulin action, and adipokine production
AU - Fontana, Luigi
AU - Klein, Samuel
AU - Holloszy, John O.
N1 - Funding Information:
Funding/support This study was supported by Grant Number UL1 RR024992 from the National Center for Research Resources (a component of the National Institutes of Health and NIH Roadmap for Medical Research), by Istituto Superiore di Sanità/ National Institutes of Health Collaboration Program Grant, a grant from the Longer Life Foundation (an RGA/Washington University Partnership), and a donation from the Scott and Annie Appleby Charitable Trust.
PY - 2010/3
Y1 - 2010/3
N2 - Calorie restriction (CR) slows aging and is thought to improve insulin sensitivity in laboratory animals. In contrast, decreased insulin signaling and/or mild insulin resistance paradoxically extends maximal lifespan in various genetic animal models of longevity. Nothing is known regarding the long-term effects of CR on glucose tolerance and insulin action in lean healthy humans. In this study we evaluated body composition, glucose, and insulin responses to an oral glucose tolerance test and serum adipokines levels in 28 volunteers, who had been eating a CR diet for an average of 6.9±5.5 years, (mean age 53.0±11 years), in 28 age-, sex-, and body fat-matched endurance runners (EX), and 28 age- and sex-matched sedentary controls eating Western diets (WD). We found that the CR and EX volunteers were significantly leaner than the WD volunteers. Insulin sensitivity, determined according to the HOMA-IR and the Matsuda and DeFronzo insulin sensitivity indexes, was significantly higher in the CR and EX groups than in the WD group (P=0.001). Nonetheless, despite high serum adiponectin and low inflammation, ∼40% of CR individuals exhibited an exaggerated hyperglycemic response to a glucose load. This impaired glucose tolerance is associated with lower circulating levels of IGF-1, total testosterone, and triiodothyronine, which are typical adaptations to life-extending CR in rodents.
AB - Calorie restriction (CR) slows aging and is thought to improve insulin sensitivity in laboratory animals. In contrast, decreased insulin signaling and/or mild insulin resistance paradoxically extends maximal lifespan in various genetic animal models of longevity. Nothing is known regarding the long-term effects of CR on glucose tolerance and insulin action in lean healthy humans. In this study we evaluated body composition, glucose, and insulin responses to an oral glucose tolerance test and serum adipokines levels in 28 volunteers, who had been eating a CR diet for an average of 6.9±5.5 years, (mean age 53.0±11 years), in 28 age-, sex-, and body fat-matched endurance runners (EX), and 28 age- and sex-matched sedentary controls eating Western diets (WD). We found that the CR and EX volunteers were significantly leaner than the WD volunteers. Insulin sensitivity, determined according to the HOMA-IR and the Matsuda and DeFronzo insulin sensitivity indexes, was significantly higher in the CR and EX groups than in the WD group (P=0.001). Nonetheless, despite high serum adiponectin and low inflammation, ∼40% of CR individuals exhibited an exaggerated hyperglycemic response to a glucose load. This impaired glucose tolerance is associated with lower circulating levels of IGF-1, total testosterone, and triiodothyronine, which are typical adaptations to life-extending CR in rodents.
KW - Adipokines
KW - Calorie restriction
KW - Endurance exercise
KW - Glucose tolerance
KW - Glycation
KW - Insulin action
UR - http://www.scopus.com/inward/record.url?scp=77949424755&partnerID=8YFLogxK
U2 - 10.1007/s11357-009-9118-z
DO - 10.1007/s11357-009-9118-z
M3 - Article
C2 - 19904628
AN - SCOPUS:77949424755
VL - 32
SP - 97
EP - 108
JO - Age
JF - Age
SN - 0161-9152
IS - 1
ER -