Impact of sirtuin-1 expression on H3K56 acetylation and oxidative stress: a double-blind randomized controlled trial with resveratrol supplementation

Abstract

Aims: Sirtuin-1 (SIRT-1) down-regulation in type 2 diabetes mellitus (T2DM) has been associated with epigenetic markers of oxidative stress. We herein aim to evaluate whether an increase in SIRT-1 expression affects histone 3 acetylation at the 56 lysine residue (H3K56ac) in T2DM patients randomly selected to receive either resveratrol (40 mg or 500 mg) or a placebo for 6 months. The primary outcome is changes in the H3K56ac level by variation in SIRT-1 expression and the secondary outcome is the evidence of association between SIRT-1 level, antioxidant markers (TAS), and metabolic variables.

Methods and results: At baseline, peripheral blood mononuclear cell H3K56ac values among the SIRT-1 tertiles did not differ. At trial end, SIRT-1 levels were significantly higher in patients receiving 500 mg resveratrol. At follow-up, patients were divided into tertiles of delta (trial end minus baseline) SIRT-1 value. Significant reductions in H3K56ac and body fat percentage were found in the highest tertile as were increased TAS levels. A multiple logistic regression model showed that the highest delta SIRT-1 tertile was inversely associated with variations in H3K56ac (OR = 0.66; 95% CI 0.44-0.99), TAS (OR = 1.01; 95% CI 1.00-1.02), and body fat percentage (OR = 0.75; 95% CI 0.58-0.96).

Conclusions: We provide new knowledge on H3K56ac and SIRT-1 association in T2DM. These data suggest that boosting SIRT-1 expression/activation may impact redox homeostasis in these patients. ClinicalTrials.gov Identifier NCT02244879.

Keywords: Epigenetics; PBMC; Resveratrol; Sirtuin-1.

Fig. 1

SIRT-1, H3K56ac, and p53ac protein expression in PBMCs recovered from T2DM patients submitted to resveratrol supplementation or placebo. a Cell extracts from T2DM patients’ PBMCs (subject 1–6) submitted to placebo were analyzed for SIRT-1, H3K56ac, and p53ac content at baseline (t0) and at the trial end (6 m). Protein levels were normalized to beta actin, H3 and p53 content, respectively. The values reported represent the relative amount (ra) of protein expression obtained by densitometric analysis. b Cell extracts from T2DM patients’ PBMCs (subject 7–12) submitted to resveratrol 40 mg/day supplementation (Resv40) were lysed and analyzed for SIRT-1, H3K56ac, and p53ac content at baseline (t0) and at the trial end (6 m). Protein levels were normalized to beta actin, H3 and p53 content, respectively. The values reported represent the relative amount (ra) of protein expression obtained by densitometric analysis. c Cell extracts from T2DM patients’ PBMCs (subject 13–18) submitted to resveratrol 500 mg/day supplementation (Resv500) were lysed and analyzed for SIRT-1, H3K56ac, and p53ac content at baseline (t0) and at the trial end (6 m). Protein levels were normalized to beta actin, H3, and p53 content, respectively. The values reported represent the relative amount (ra) of protein expression obtained by densitometric analysis

Fig. 2

Relative amount of SIRT-1, H3K56ac, and p53ac protein expression in PBMCs recovered from T2DM patients submitted to resveratrol supplementation or placebo. a The value reported represents the relative amount of protein expression obtained by densitometric analysis of cell extract analyzed in Fig. 1a. Cell extract from T2DM patient’ PBMCs (subject 1–6) submitted to placebo was lysed and analyzed for SIRT-1, H3K56ac, and p53ac content at baseline (t0) and at trial end (6 m). Protein levels were normalized to beta actin, H3, and p53 content, respectively. b The value reported represents the relative amount of protein expression obtained by densitometric analysis of cell extract analyzed in Fig. 1b. Cell extract from T2DM patient’ PBMCs (subject 7–12) submitted to resveratrol 40 mg/day supplementation (Resv40) was lysed and analyzed for SIRT-1, H3K56ac, and p53ac content at baseline (t0) and at trial end (6 m). Protein levels were normalized to beta actin, H3, and p53 content, respectively. c The value reported represents the relative amount of protein expression obtained by densitometric analysis of cell extract analyzed in Fig. 1c. Cell extract from T2DM patient’ PBMCs (subject 13–18) submitted to resveratrol 500 mg/day supplementation (Resv500) was lysed and analyzed for SIRT-1, H3K56ac, and p53ac content at baseline (t0) and at trial end (6 m). Protein levels were normalized to beta actin, H3, and p53 content, respectively