TY - JOUR
T1 - Blood DNA Methylation at TXNIP and Glycemic Changes in Response to Weight-Loss Diet Interventions
T2 - the POUNDS lost trial
AU - Li, Xiang
AU - Shao, Xiaojian
AU - Bazzano, Lydia A.
AU - Xue, Qiaochu
AU - Koseva, Boryana S.
AU - Grundberg, Elin
AU - Shai, Iris
AU - Bray, George A.
AU - Sacks, Frank M.
AU - Qi, Lu
N1 - Funding Information: The authors thank all the POUNDS Lost participants for their dedication and contribution to the research. The study was supported by grants from the National Heart, Lung, and Blood Institute (HL071981, HL034594, HL126024), the National Institute of Diabetes and Digestive and Kidney Diseases (DK115679, DK091718, DK100383), the Fogarty International Center (TW010790), and Tulane Research Centers of Excellence Awards. Xiang Li was the recipient of the American Heart Association Predoctoral Fellowship Award (19PRE34380036). Publisher Copyright: © 2022, The Author(s), under exclusive licence to Springer Nature Limited.
PY - 2022/2/14
Y1 - 2022/2/14
N2 - BACKGROUND: Thioredoxin Interacting Protein (TXNIP) functions as a master regulator for glucose homeostasis. Hypomethylation at the 5'-cytosine-phosphate-guanine-3' (CpG) site cg19693031 of TXNIP has been consistently related to islet dysfunction, hyperglycemia, and type 2 diabetes. DNA methylation (DNAm) may reveal the missing mechanistic link between obesity and type 2 diabetes. We hypothesize that baseline DNAm level at TXNIP in blood may be associated with glycemic traits and their changes in response to weight-loss diet interventions.METHODS: We included 639 adult participants with overweight or obesity, who participated in a 2-year randomized weight-loss diet intervention. Baseline blood DNAm levels were profiled by high-resolution methylC-capture sequencing. We defined the regional DNAm level of TXNIP as the average methylation level over CpGs within 500 bp of cg19693031. Generalized linear regression models were used for main analyses.RESULTS: We found that higher regional DNAm at TXNIP was significantly correlated with lower fasting glucose, HbA1c, and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) at baseline (P < 0.05 for all). Significant interactions were observed between dietary protein intake and DNAm on changes in insulin (P-interaction = 0.007) and HOMA-IR (P-interaction = 0.009) at 6 months. In participants with the highest tertile of regional DNAm at TXNIP, average protein (15%) intake was associated with a greater reduction in insulin (β: -0.14; 95% CI: -0.24, -0.03; P = 0.011) and HOMA-IR (β: -0.15; 95% CI: -0.26, -0.03; P = 0.014) than high protein (25%) intake, whereas no significant associations were found in those with the lower tertiles (P > 0.05). The interaction was attenuated to be non-significant at 2 years, presumably related to decreasing adherence to the diet intervention.CONCLUSIONS: Our data indicate that higher regional DNAm level at TXNIP was significantly associated with better fasting glucose, HbA1c, and HOMA-IR; and people with higher regional DNAm levels benefited more in insulin and HOMA-IR improvement by taking the average-protein weight-loss diet.
AB - BACKGROUND: Thioredoxin Interacting Protein (TXNIP) functions as a master regulator for glucose homeostasis. Hypomethylation at the 5'-cytosine-phosphate-guanine-3' (CpG) site cg19693031 of TXNIP has been consistently related to islet dysfunction, hyperglycemia, and type 2 diabetes. DNA methylation (DNAm) may reveal the missing mechanistic link between obesity and type 2 diabetes. We hypothesize that baseline DNAm level at TXNIP in blood may be associated with glycemic traits and their changes in response to weight-loss diet interventions.METHODS: We included 639 adult participants with overweight or obesity, who participated in a 2-year randomized weight-loss diet intervention. Baseline blood DNAm levels were profiled by high-resolution methylC-capture sequencing. We defined the regional DNAm level of TXNIP as the average methylation level over CpGs within 500 bp of cg19693031. Generalized linear regression models were used for main analyses.RESULTS: We found that higher regional DNAm at TXNIP was significantly correlated with lower fasting glucose, HbA1c, and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) at baseline (P < 0.05 for all). Significant interactions were observed between dietary protein intake and DNAm on changes in insulin (P-interaction = 0.007) and HOMA-IR (P-interaction = 0.009) at 6 months. In participants with the highest tertile of regional DNAm at TXNIP, average protein (15%) intake was associated with a greater reduction in insulin (β: -0.14; 95% CI: -0.24, -0.03; P = 0.011) and HOMA-IR (β: -0.15; 95% CI: -0.26, -0.03; P = 0.014) than high protein (25%) intake, whereas no significant associations were found in those with the lower tertiles (P > 0.05). The interaction was attenuated to be non-significant at 2 years, presumably related to decreasing adherence to the diet intervention.CONCLUSIONS: Our data indicate that higher regional DNAm level at TXNIP was significantly associated with better fasting glucose, HbA1c, and HOMA-IR; and people with higher regional DNAm levels benefited more in insulin and HOMA-IR improvement by taking the average-protein weight-loss diet.
UR - http://www.scopus.com/inward/record.url?scp=85124726349&partnerID=8YFLogxK
U2 - https://doi.org/10.1038/s41366-022-01084-5
DO - https://doi.org/10.1038/s41366-022-01084-5
M3 - Article
C2 - 35165382
SN - 0307-0565
VL - 46
SP - 1122
EP - 1127
JO - International Journal of Obesity
JF - International Journal of Obesity
IS - 6
ER -
