Association Between Promoter Methylation of Vitamin D Metabolic Pathway Genes and Tuberculosis and Diabetes Comorbidity in a Chinese Han Population: A Case–Control Study

Figures & data

Figure 1 Chest radiograph sign in pulmonary window and mediastinal. (A) Air bronchial sign. (B) Single cavity. (C) Multiple cavities.

Table 1 General Characteristics and Clinical Parameters of Cases and Controls

Variables	Case	Control	P value
	N=50	N=50
Age (year)	56.4 (11.1)	55.8 (9.49)	0.787
Female, n (%)	9 (18%)	9 (18%)
BMI (kg/m^2)	21.8 (2.58)	24.3 (3.25)	<0.001
PLT (× 109/L)	287 [234;378]	216 [191;250]	<0.001
PCT (%)	0.24 [0.22;0.29]	0.24 [0.22;0.28]	0.994
PDW (fL)	15.7 [15.4;16.1]	13.2 [12.2;14.6]	<0.001
MPV (fL)	8.35 [7.80;9.28]	10.9 [10.3;11.6]	<0.001
TG (mg/dl)	132 [100;163]	105 [75.5;182]	0.177
HDL (mg/dl)	32.1 [27.9;37.9]	51.6 [47.2;61.8]	<0.001
LDL (mg/dl)	102 (26.0)	133 (26.5)	<0.001
TCHOL (mg/dl)	157 (36.0)	211 (32.9)	<0.001
Sbp (mmHg)	123 (17.1)	137 (17.4)	<0.001
Dbp (mmHg)	75.9 (12.3)	83.3 (9.62)	0.001
GLU (mg/dl)	167 [121;201]	98.8 [94.7;105]	<0.001
25(OH)D ng/mL	24.3 [20.6;27.2]	29.5 [26.2;33.1]	<0.001
Overall methylation (%)
CYP24A1	3.29 [2.94;3.71]	3.80 [3.49;4.01]	<0.001
CYP2R1	0.67 [0.64;0.70]	0.68 [0.64;0.72]	0.270
CYP27B1	3.84 [3.36;4.62]	5.05 [4.53;5.87]	<0.001
DHCR7	2.50 [2.35;2.68]	2.77 [2.55;2.98]	<0.001
VDR	1.67 [1.48;1.83]	2.05 [1.88;2.28]	<0.001

Notes: Normal variables are expressed as mean ± standard deviation (SD), and skewed variables are expressed as median (interquartile range). P < 0.05 was statistically significant.

Abbreviations: BMI, body mass index; PLT, platelet; PCT, thrombocytocrit; MPV, mean platelet volume; PDW, platelet distribution width; TG, triglyceride; HDL, high-density lipoprotein; LDT, low-density lipoprotein; TCHOL, total cholesterol; SBP, systolic blood pressure systolic pressure; DBP, diastolic blood pressure; GLU, fasting glucose.

Table 2 Association of DNA Methylation Level of Candidate Genes and Risk of TB-DM

Genes	Crude Model	Adjusted Model^a
	OR (95% CI)	OR (95% CI)
CYP24A1	0.286 (0.117–0.699)	0.343 (0.144–0.821)
CYP27B1	0.407 (0.245–0.679)	0.461 (0.275–0.773)
DHCR7	0.062 (0.012–0.327)	0.090 (0.015–0.530)
VDR	0.004 (0.0002–0.074)	0.006 (0.0003–0.115)

Notes: ^aAdjusted for age and BMI.

Figure 2 Methylation analyses of CpG islands of key genes promoter in patients with TB-DM and health subject. (A) Methylation analyses of two CpG islands of the VDR promoter in Peripheral blood mononuclear cells (PBMCs) from patients and Health subject. (B) Methylation analyses of two CpG islands of the DHCR7 promoter in Peripheral blood mononuclear cells (PBMCs) from patients and Health subject. (C) Methylation analyses of one CpG islands of the CYP27B1 promoter in Peripheral blood mononuclear cells (PBMCs) from patients and Health subject. (D) Methylation analyses of four CpG islands of the CYP27A1 promoter in Peripheral blood mononuclear cells (PBMCs) from patients and Health subject. (E) Methylation analyses of two CpG islands of the CYP2R1 promoter in Peripheral blood mononuclear cells (PBMCs) from patients and Health subject (*p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001, and ns refers to no significant).

Figure 3 The overall methylation of candidate genes promoter in patients with TB-DM and health subject. (A) CYP24A1; (B) CYP27B1; (C) CYP2R1; (D) DHCR7; (E) VDR (***p < 0.001, and ns refers to no significant).

Table 3 Diagnostic Values of Genes for TB-DM

Gene	AUC	95% CI	Sensitivity	Specificity
CYP24A1	0.7484	0.648–0.849	0.72	0.74
CYP27B1	0.774	0.681–0.867	0.68	0.78
DHCR7	0.7304	0.632–0.829	0.68	0.68
VDR	0.8544	0.778–0.931	0.64	0.96
Combined	0.8632	0.791–0.935	0.64	0.94

Figure 4 The ROC curve of the methylation levels of candidate genes.

Table 4 Methylation Levels of Genes in TB-DM According to Vitamin D Status

Genes	VDS	VDI	VDD	P value	VDS vs VDI	VDS vs VDD	VDI vs VDD
	N=7	N=32	N=11
CYP24A1	3.39 [3.17;3.99]	3.47 [3.21;3.78]	2.89 [2.62;3.05]	0.001	0.971	0.019	<0.001
CYP27B1	3.76 [3.41;4.87]	4.15 [3.53;4.71]	3.18 [2.77;3.78]	0.025	0.558	0.203	0.021
DHCR7	2.46 [2.37;2.94]	2.58 [2.43;2.69]	2.26 [2.01;2.42]	0.007	0.855	0.095	0.005
VDR	1.70 [1.58;1.81]	1.67 [1.50;1.84]	1.61 [1.46;1.69]	0.466	1.000	0.417	0.417

Abbreviations: VDD, vitamin D deficiency; VDI, vitamin D insufficiency; VDS, vitamin D sufficiency.

Figure 5 Corrplot of studied correlation of methylation level of key genes in vitamin D metabolic pathway and with biochemical parameters in TB-DM. Blue colour represents positive correlation; red colour represents negative correlation; darker colors and larger shapes represent higher association. Blank represents no statistical difference.