LINE-1 methylation levels, a biomarker of weight loss in obese subjects, are influenced by dietary antioxidant capacity

Figures & data

Table 1 Anthropometric and biochemical changes after 8 weeks of treatment depending on the diet

Variable	AHA (n = 48)	RESMENA (n = 48)	P
Sex (%)			ns
Male	56.3	50.0
Female	43.7	50.0
ΔWeight (kg)	−6.7 (−7.6 to −5.8)	−7.1 (−7.9 to −6.3)	0.555
ΔBMI (kg/m^2)	−2.4 (−2.7 to −2.1)	−2.5 (−2.8 to −2.2)	0.732
ΔWaist (cm)	−6.8 (−8.2 to −5.4)	−7.5 (−8.6 to −6.4)	0.432
ΔTotal fat mass by DXA (kg)	−4.6 (−5.3 to −3.9)	−5.2 (−5.9 to −4.5)	0.208
ΔTrunk mass by DXA (kg)	−2.6 (−4.1 to −1.1)	−3.7 (−4.3 to −3.1)	0.183
ΔSBP (mmHg)	−11 (−16 to −6)	−13 (−19 to −7)	0.570
ΔDBP (mmHg)	−6 (−9 to −3)	−8 (−11 to −5)	0.371
ΔTotal cholesterol (mg/dl)	−16.9 (−26.6 to −7.2)	−16.3 (−29.9 to −2.7)	0.943
ΔHDL-c (mg/dl)	−4.0 (−6.1 to −1.9)	−2.0 (−3.9 to −0.1)	0.158
ΔGlucose (mg/dl)	−13.0 (−21.8 to −4.2)	−13.6 (−24.6 to −2.6)	0.939
ΔTG (mg/dl)	−30.9 (−51.5 to −10.3)	−43.5 (−66.6 to −20.4)	0.421

Data expressed as mean (95% CI). Abbreviations: BMI, body mass index; DXA, dual-energy X-ray absorptiometry; SBP, systolic blood pressure; DBP, diastolic blood pressure; HDL-c, high density lipoprotein cholesterol; TG, triglycerides.

Table 2 Characteristics of the population classified by the response to the energy-restricted dietary program

Variable	Low responders (n = 58)		High responders (n = 38)		P ^†
	Baseline	8 weeks	Baseline	8 weeks
Age (years)	48 (45.4–50.6)	48 (45.4–50.6)	51 (48.0–54.0)	51 (48.0–54.0)	0.133
Sex (%)					0.938
Male	53.4	53.4	52.6	52.6
Female	46.6	46.6	47.5	47.5
Weight (kg)	101.2 (96.0–106.2)	96.0 (91.2–100.8)***	97.4 (92.4–102.4)	88.0 (83.5–92.5)***	<0.001
BMI (kg/m^2)	36.0 (34.8–37.2)	34.2 (33.1–35.3)***	35.5 (33.9–37.1)	32.1 (30.6–33.6)***	<0.001
Waist circumference (cm)	111.7 (108.2–115.2)	106.2 (103.1–109.3)***	110.2 (106.2–114.2)	100.6 (96.9–104.3)***	<0.001
Total fat mass (kg)^‡	43.3 (40.9–45.7)	39.4 (37.0–41.8)**	40.9 (37.5–44.3)	34.3 (31.2–37.4)***	<0.001
Trunk mass (kg)^‡	25.5 (23.8–27.2)	23.4 (21.7–25.1)**	24.9 (22.8–27.0)	20.1 (18.2–22.0)***	0.001
SBP (mmHg)	147 (143–151)	138 (134–142)***	153 (145–161)	136 (130–142)***	<0.05
DBP (mmHg)	85 (83–87)	79 (77–81)***	85 (81–89)	77 (74–80)***	0.122
TC (mg/dl)	214.2 (202.4–226)	204.3 (193.1–214.9)	229.1 (215.8–242.4)	202.1 (187.5–216.7)***	<0.05
HDL-c (mg/dl)	44.4 (41.6–47.2)	42.4 (39.7–45–1)	45.1 (42.2–48.0)	40.7 (38.3–43.1)**	0.126
Glucose (mg/dl)^§	123.9 (113.6–134.2)	111.0 (105.9–116.1)**	120.2 (110.2–130.2)	106.4 (98.9–113.9)***	0.945
TG (mg/dl)^§	180.8 (151.9–209.7)	154.0 (132.8–175.2)**	191.7 (156.6–226.8)	137.1 (106.7–167.5)***	0.797
Energy intake (kcal)	2111 (1970–2252)	1383 (1297–1469)***	2311 (2158–2464)	1291 (1224–1358)***	<0.01
Dietary TAC (mmol/day)	7.5 (6.7–8.3)	9.8 (7.9–9.7)***	7.0 (6.0–8.0)	11.2 (10.0–12.4)***	0.159

Data expressed as mean (95% CI). Abbreviations: BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; TC, total cholesterol; HDL-c, high density lipoprotein cholesterol; TG, triglycerides; TAC, total antioxidant capacity. High responders categorized by 8% body weight loss from baseline.

^† P of variable changes between high responders and low responders.

*P < 0.05 between baseline and 8 weeks after.

**P < 0.01 between baseline and 8 weeks after.

***P < 0.001 between baseline and 8 weeks after.

^‡Measurement by dual-energy X-ray absorptiometry (DXA).

^§Non-normally distributed variables were transformed for the model analysis.

Figure 1 Baseline DNA methylation levels of low and high responders to the intervention. (A) Baseline DNA methylation levels (%) of low responders and high responders adjusted for age, gender, and number of plate. P from ANCOVA test: *0.05 < P < 0.01; ***P < 0.001. (B) Pearson's correlation between total fat mass loss (kg) and baseline DNA methylation levels (%) of LINE-1; (C) Pearson's correlation between body weight loss (as kg) and baseline DNA methylation levels (%) of LINE-1. r ² represents Pearson correlation coefficient and P is the stringency of the correlation. A P < 0.05 was considered statistically significant. Full circles: LR; empty circles: HR.

Figure 2 Pearson's correlation between baseline methylation levels (%) of LINE-1 and baseline dietary total antioxidant capacity (TAC; mmol/day), adjusted for age, sex, diet type, energy intake, and number of plate. r ² represents Pearson correlation coefficient.

Table 3 Multiple regression analyses showing the independent contributions of studied domains* to the variation of baseline DNA methylation of LINE-1

LINE-1 as dependent	B coefficient	95% confidence interval	P
Total fat mass by DXA (%)	−0.379	(−0.608; −0.167)	0.001
Dietary TAC (mmol/day)	0.290	(0.156; 1.053)	0.007
R ^2 = 0.22 (P < 0.001)

Adjusted R ² and all independent variables included in each model are presented in the table. Italic style represents statistical significant P values.

*Domains are adiposity indicators (baseline total fat mass by DXA (%) and baseline dietary total antioxidant capacity (mmol/day)).