Figure 1.
Rhythmic expression of CLOCK (1A), PER2 (1B) and BMAL1 (1C) in human subcutaneous (S) and visceral (V) adipose tissue (AT) (Control samples).
Adipose depots were isolated at 4-h intervals over the course of the day from adipose tissue cultures (time at ZT0 (1000 h), ZT4 (1400 h), ZT8 (1800 h), ZT12 (2200 h), ZT16 (0200 h) and ZT20 hours (0600 h)). Raw data (not mesor corrected) are represented by six black dots. Solid lines represent the estimated 24 h sinusoidal curve, in the population. CLOCK, PER2 and BMAL1 expression among different times of culture and statistical differences were analyzed in both depots (VAT and SAT) (repeated measures ANOVA test P<0.05) evidences changes in gene expression due to time. Data of relative expression are represented as Arbitrary Units (AU). Data are reported as means ± S.E.M.
Table 1.
Parameters imputed from periodic regression analysis for genes studied.
Figure 2.
Polar (clock-like) representation of the estimates of the parameters of the rhythm for CLOCK, PER2 and BMAL1 in subcutaneous (2A) and visceral (2B) adipose tissue.
In the graphs the circles represent 24 hours and the radius corresponds to 10 units. The vector length is the amplitude of the rhythm and it points to its acrophase. Dotted circles are the join 95% confidence limits for the vectors (if limits include the centre, the rhythm is not statistically significant), and dotted lines are the corresponding confidence interval for the acrophase. The population rhythms in control subcutaneous (S) and visceral (V) are clearly visible and statistically significant in both genes studied.
Figure 3.
Polar (clock-like) representation of the estimates of the parameters of the rhythm for CLOCK, PER2 and BMAL1 in dexamethasone treated groups.
In graphs 3A, 3B and 3C the circles represent 24 hours while in 3D, 3E and 3F it represents 12 hours, and the radius corresponds to 5 units. The vector length is the amplitude of the rhythm and it points to its acrophase. Dotted circles are the join 95% confidence limits for the vectors (if limits include the centre, the rhythm is not statistically significant), and dotted lines are the corresponding confidence interval for the acrophase. In 3A, 3B and 3C the absence of 24 hours rhythmicity is evident except for the subcutaneous PER2 and BMAL1 that is statistically significant. In 3D, 3E and 3F the presence of an approximately 12 hours oscillation is evidenced in all treated groups.
Figure 4.
Effect of acute dexamethasone exposure on circadian expression of CLOCK (1A), PER2 (1B) and BMAL1 (1C) in human subcutaneous (S) and visceral (V) adipose tissue (DEX samples).
Adipose depots were isolated at 4-h intervals over the course of the day from adipose tissue cultures (time at ZT0 (1000 h), ZT4 (1400 h), ZT8 (1800 h), ZT12 (2200 h), ZT16 (0200 h) and ZT20 hours (0600 h)). Raw data (not mesor corrected) are represented by six black dots. Solid and gray lines represent the fitted 12 h sinusoidal curve. Differences on the expression among different times of culture and statistical differences were analyzed in both depots (VAT and SAT) (repeated measures ANOVA test, P<0.05) evidences changes in time. Data of relative expression are represented as Arbitrary Units (AU). Data are reported as means ± S.E.M.