Fig. 3: Feeding increases serum Lac-Phe concentrations.
From: Metformin and feeding increase levels of the appetite-suppressing metabolite Lac-Phe in humans
a,b, Lac-Phe levels in T2D volunteers with (a) or without (b) metformin treatment (sample sizes indicated) and under fasted (blue bars) and non-fasted (red bars) conditions, where volunteers had eaten within 6 h (*P = 0.034). c, Lac-Phe levels 30 min before and 1 h after a standardized MMT involving non-T2D (n = 10), pre-T2D (n = 10) and T2D (n = 10) volunteers. Each volunteer completed the test on three separate days, resulting in a total of 90 paired samples (n = 30 for each group) (****P < 0.0001). d, Lac-Phe levels after a volunteer’s habitual meal (n = 24) or high-fat meal (n = 48), relative to fasted levels, in 24 overweight/obese sedentary men. Serum samples were taken before breakfast and approximately 45 min after dinner (****P < 0.0001). e, Lac-Phe levels after feeding with liquid glucose or dates. Left, Khalas date nutritional information is given for reference. Twenty-one participants undertook three separate dietary challenges, consuming either a glucose solution (OGTT, n = 21) or ten fruits of the Deglet Nour (n = 21) or Khalas (n = 20, one volunteer did not participate) date varieties. Blood samples were collected before intake and at intervals up to 120 min afterward. Lac-Phe levels were normalized to fasting levels. The AUC is shown. Data are violin plots with median (dashed line) plus maximum and minimum quartiles (dotted line) (a,b), individual paired data points (c), mean (dotted line) and individual data points (d) and mean ± s.e.m. (e). Data were analysed using two-sided Studentʼs t-test (a,b), two-way ANOVA with Sidakʼs post test (c) or Tukeyʼs post test (e) or one-sample t-test against a theoretical value of 1 (d).
