title: Subchronic sleep restriction causes tissue-specific insulin resistance.
abstract: BACKGROUND
  Short sleep duration is associated with an increased risk of type 2 diabetes. Subchronic sleep restriction (SR) causes insulin resistance, but the mechanisms and roles of specific tissues are unclear.
  
  
  OBJECTIVE
  The purpose of this article was to determine whether subchronic SR altered (1) hepatic insulin sensitivity, (2) peripheral insulin sensitivity, and (3) substrate utilization.
  
  
  METHODS
  This was a randomized crossover study in which 14 subjects underwent 2 admissions separated by a washout period. Each admission had 2 acclimatization nights followed by 5 nights of either SR (4 hours time in bed) or normal sleep (8 hours time in bed). MAIN OUTCOME MEASURE/METHODS: Insulin sensitivity (measured by hyperinsulinemic-euglycemic clamp) and hepatic insulin sensitivity (measured by stable isotope techniques) were measured. In addition, we assayed stress hormone (24-hour urine free cortisol, metanephrine, and normetanephrine), nonesterified fatty acid (NEFA), and β-hydroxybutyrate (β-OH butyrate) levels. Resting energy expenditure (REE) and respiratory quotient (RQ) were measured by indirect calorimetry.
  
  
  RESULTS
  Compared to normal sleep, whole-body insulin sensitivity decreased by 25% (P = .008) with SR and peripheral insulin sensitivity decreased by 29% (P = .003). Whereas hepatic insulin sensitivity (endogenous glucose production) did not change significantly, percent gluconeogenesis increased (P = .03). Stress hormones increased modestly (cortisol by 21%, P = .04; metanephrine by 8%, P = .014; normetanephrine by 18%, P = .002). Fasting NEFA and β-OH butyrate levels increased substantially (62% and 55%, respectively). REE did not change (P = 0.98), but RQ decreased (0.81 ± .02 vs 0.75 ± 0.02, P = .045).
  
  
  CONCLUSIONS
  Subchronic SR causes unique metabolic disturbances characterized by peripheral, but not hepatic, insulin resistance; this was associated with a robust increase in fasting NEFA levels (indicative of increased lipolysis), decreased RQ, and increased β-OH butyrate levels (indicative of whole-body and hepatic fat oxidation, respectively). We postulate that elevated NEFA levels are partially responsible for the decrease in peripheral sensitivity and modulation of hepatic metabolism (ie, increase in gluconeogenesis without increase in endogenous glucose production). Elevated cortisol and metanephrine levels may contribute to insulin resistance by increasing lipolysis and NEFA levels.
authors: San Francisco Veterans Affairs Medical Center (M.N.R., T.C.N., C.G.), San Francisco, California 94121; Department of Medicine (M.N.R., C.G., K.M., M.S., J.-M.S.), Division of Endocrinology and Metabolism and Department of Psychiatry (T.C.N.), University of California, San Francisco, San Francisco, California 94143; and Touro University (J.-M.S.), Vallejo, California 94592.
authors: Madhu N
authors: MN
authors: Rao
authors: Thomas C
authors: TC
authors: Neylan
authors: Carl
authors: C
authors: Grunfeld
authors: Kathleen
authors: K
authors: Mulligan
authors: Morris
authors: M
authors: Schambelan
authors: Jean-Marc
authors: JM
authors: Schwarz
mesh_terms: D000328:Adult; D002908:Chronic Disease; D018592:Cross-Over Studies; D005260:Female; D005947:Glucose / Q000378:metabolism; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance; D008099:Liver / Q000378:metabolism; D008297:Male; D009928:Organ Specificity; D012890:Sleep / Q000502:physiology; D012892:Sleep Deprivation / Q000378:metabolism*; D055815:Young Adult
chemical_list: D005947:Glucose