Effect of sleep deprivation on cholesterol metabolism and triglyceridaemia in male volunteers.
The effect of 5-day sleep deprivation (SD) on cholesterol metabolism, together with triglyceridaemia, was studied in seven healthy male volunteers. A 3-day control period was followed by 5 days (120 h) complete SD and 4 days recovery. Blood was collected at 9 a.m. and at 9 p.m. Vastus lateralis muscle biopsy was performed during the control period, on the 5th day of SD, and on day 3 of recovery. The value of muscle cholesterol was related to the non-collagen protein content. The plasma triglycerides (TG) varied in a circadian biorhythm, the amplitude of which declined gradually during SD. The morning triglyceridaemia was significantly decreased on days 3-5 of SD (35%-79% of initial values). On days 4 and 5 of SD, plasma cholesterol fell significantly to 78% and 88% of control values, respectively. The ratio of its esterified to unesterified fractions remained unchanged throughout SD. Basal activity of lecithin cholesterol acyltransferase (LCAT) showed no diurnal biorhythm; on the last 2 days of SD, LCAT activity fell significantly to 71%-80%. In contrast, the decrease in fractional esterification rate (FER) was insignificant. In the vastus lateralis muscle, total cholesterol (TC) was decreased by 40% at the end of SD, the reduction being greater for cholesterol esters (CE) (by 63%) than for free cholesterol (FC) (by 36%). The relative proportion of CE significantly decreased from an initial 14.7% to 9.2% on the last day of SD. During recovery after SD, plasma cholesterol and TG slowly returned to normal. LCAT activity and FER recovered quickly, within 48 h.(ABSTRACT TRUNCATED AT 250 WORDS)
Vondra
K
K
Brodan
V
V
Dobiásová
M
M
Vítek
V
V
Kopecká
J
J
D000328:Adult; D002784:Cholesterol / Q000378:metabolism*; D002788:Cholesterol Esters / Q000097:blood; D002940:Circadian Rhythm; D004951:Esterification; D006801:Humans; D008297:Male; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000378:metabolism; D012892:Sleep Deprivation / Q000502:physiology*; D014280:Triglycerides / Q000097:blood*
D002788:Cholesterol Esters; D014280:Triglycerides; D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase