The relative expressions of microRNAs 486, 146b and 15b and serum levels of betatrophin were significantly higher in G3 and G2 when compared with G1 and in G3 when compared with G2 (table 1). Similar results were found regarding BMI percentile, the levels of serum glucose, insulin, C-peptide, HbA1c%, and triacylglycerol (table 1).
Table 1: Comparison of different studied variables (mean ± SD) among G1, G2 and G3
|
G1
(healthy, n=50)
|
G2
(obese, n=35)
|
G3
(obese with T2DM, n=35)
|
p-Value
|
G1Vs G2 Vs G3
|
G2 Vs G1
|
G3 Vs G1
|
G3 Vs G2
|
Age (years)
|
9.31±1.47
|
9±1.77
|
9.59±1.40
|
0.273
|
0.38
|
0.36
|
0.12
|
Gender
· Male
· Female
|
31 (62%)
19 (38%)
|
27 (77%)
8 (23%)
|
22 (63%)
13 (37%)
|
0.294
|
0.16
|
0.78
|
0.29
|
BMI percentile
|
81.0±1.2
|
96.8±1.6
|
96.7±1.4
|
<0.001
|
<0.001
|
<0.001
|
0.935
|
Glucose (mg/dL)
|
96.46±8.78
|
101±15.40
|
116.65±18.76
|
0.006
|
0.08
|
0.004
|
0.04
|
Insulin (μg/mL)
|
10.16±1.48
|
10.50±0.69
|
11.20±0.93
|
0.037
|
0.20
|
0.002
|
0.014
|
C-Peptide(ng/mL)
|
2.98±0.43
|
3.13±0.21
|
3.21±0.28
|
0.007
|
0.02
|
0.008
|
0.09
|
HbA1c (%)
|
4.17±0.21
|
4.85±0.99
|
7.32±2.62
|
<0.001
|
<0.001
|
<0.001
|
<0.001
|
Cholesterol (mg/dL)
|
188.79±21.26
|
190.14±26.75
|
196.45±26.49
|
0.34
|
0.79
|
0.14
|
0.32
|
HDLc (mg/dL)
|
39.30±1.82
|
36.91±8.12
|
35.61±10.40
|
0.06
|
0.09
|
0.04
|
0.55
|
LDLc (mg/dL)
|
127.43±20.12
|
131.39±25.95
|
135.72±22.23
|
0.252
|
0.43
|
0.08
|
0.45
|
TAG (mg/dL)
|
110.32±22.43
|
111.17±18.56
|
125.61±20.65
|
0.001
|
0.80
|
0.002
|
0.001
|
miR-486R
|
1.52±0.38
|
2.11±0.25
|
2.71±0.29
|
0.002
|
0.003
|
<0.001
|
0.001
|
miR-146bR
|
2.42±0.58
|
3.01±0.18
|
3.54±0.24
|
<0.001
|
<0.001
|
<0.001
|
<0.001
|
miR-15bR
|
3.82±0.56
|
4.32±0.27
|
5.10±0.36
|
<0.001
|
<0.001
|
<0.001
|
<0.001
|
Betatrophin (ng/mL)
|
47.17±6.85
|
54.54±17.67
|
71.68±29.63
|
<0.001
|
<0.001
|
<0.001
|
<0.001
|
SD: standard deviation, T2DM: type 2 diabetes mellitus, BMI: body mass index, HDLc: high density lipoprotein cholesterol, LDLc: low density lipoprotein cholesterol, HbA1c: glycated hemoglobin, TAC: triacylglycerol, microR-486R: microRNA 486 relative expression, miR-146bR: microRNA 146b relative expression, miR-15bR: microRNA 15b relative expression.
Correlations (table 2, Figures 1 &2)
Correlation of circulating microRNAs relative expressions and serum betatrophin levels with the other studied parameters in the three groups is shown in table (2).
miR-486R showed significant positive correlations with BMI percentile and with fasting serum glucose levels (G1, G2 and G3), with HBA1c% (G2 and G3) and with triacylglycerols (G3). On the other hand, it showed significant negative correlations with HDLc (G2), with serum insulin levels (G1, G2 and G3) and with serum C-peptide levels (G2 and G3).
miR-146bR showed significant positive correlations showed significant positive correlations with BMI percentile, with fasting serum glucose levels and with HBA1c% (G2 and G3) and with triacylglycerols (G3). While, it showed significant negative correlations with HDLc (G2), with serum insulin levels and with serum C-peptide levels (G2 and G3).
miR-15bR showed significant positive correlations showed significant positive correlations with BMI percentile, and with fasting serum glucose levels (G2 and G3), and with HBA1c% (G1, G2 and G3). These relative expressions showed significant negative correlations with HDLc (G2), with serum insulin levels (G1, G2 and G3) and with serum C-peptide levels (G2 and G3).
Serum betatrophin levels showed significant positive correlations showed significant positive correlations with BMI percentile, with fasting serum glucose levels, and with HBA1c% (G1, G2 and G3) and with TAG levels (G3). On the other hand, these levels showed significant negative correlations with serum insulin levels and with serum C-peptide levels (G3).
The significant correlations among serum betatrophin levels and the relative expressions of miR-486, -146b and 15b in G2 and G3 are shown in figure 1 and 2. Non-significant correlations were noticed among them in G1.
Table 2: Correlation of circulating microRNAs relative expressions and serum betatrophin levels with the other studied parameters in the three groups
|
BMI percentile
|
Cholesterol (mg/dL)
|
Glucose (mg/dL)
|
HDLc (mg/dL)
|
LDLc (mg/L)
|
HbA1c (%)
|
TAG (mg/dL)
|
Insulin (μg/mL)
|
C-Peptide (ng/mL)
|
G1
(healthy, n=50)
|
miR-486R
|
r
|
0.282*
|
0.205
|
0.323*
|
0.078
|
0.167
|
0.271
|
0.190
|
-0.293*
|
-0.176
|
p
|
0.048
|
0.154
|
0.022
|
0.590
|
0.247
|
0.057
|
0.186
|
0.039
|
0.223
|
miR-146bR
|
r
|
-0.056
|
-0.014
|
0.049
|
0.126
|
-0.043
|
-0.171
|
0.075
|
-0.135
|
-0.156
|
p
|
0.701
|
0.921
|
0.736
|
0.383
|
0.765
|
0.235
|
0.604
|
0.351
|
0.279
|
miR-15bR
|
r
|
0.254
|
0.088
|
0.130
|
0.104
|
0.067
|
0.377**
|
0.073
|
-0.450**
|
-0.235
|
p
|
0.075
|
0.546
|
0.368
|
0.472
|
0.645
|
0.007
|
0.616
|
0.001
|
0.100
|
Betatrophin (ng/mL)
|
r
|
0.335*
|
-0.087
|
0.339*
|
-0.196
|
-0.013
|
0.316**
|
-0.275
|
0.064
|
0.053
|
p
|
0.017
|
0.548
|
0.016
|
0.172
|
0.930
|
0.049
|
0.063
|
0.661
|
0.713
|
G2
(obese, n=35)
|
miR-486R
|
r
|
0.335*
|
0.073
|
0.691**
|
-0.510**
|
0.238
|
0.785**
|
-0.022
|
-0.554**
|
-0.424*
|
p
|
0.049
|
0.675
|
0.000
|
0.002
|
0.168
|
0.000
|
0.902
|
0.001
|
0.011
|
miR-146bR
|
r
|
0.673*
|
-0.288
|
0.397*
|
-0.362*
|
-0.154
|
0.493**
|
-0.205
|
-0.314**
|
-0.332*
|
p
|
0.000
|
0.094
|
0.018
|
0.033
|
0.378
|
0.003
|
0.237
|
0.046
|
0.041
|
miR-15bR
|
r
|
0.454*
|
-0.291
|
0.483**
|
-0.359*
|
-0.152
|
0.551**
|
-0.249
|
-0.359*
|
-0.344*
|
p
|
0.018
|
0.090
|
0.003
|
0.034
|
0.383
|
0.001
|
0.150
|
0.034
|
0.043
|
Betatrophin (ng/mL)
|
r
|
0.376*
|
-0.293
|
0.392*
|
-0.242
|
-0.206
|
0.363*
|
-0.146
|
-0.237
|
-0.124
|
p
|
0.026
|
0.087
|
0.020
|
0.161
|
0.236
|
0.041
|
0.403
|
0.171
|
0.579
|
G3
(obese with T2DM, n=35)
|
miR-486R
|
r
|
0.446**
|
0.086
|
0.564**
|
0.125
|
0.032
|
0.561**
|
0.785**
|
-0.371*
|
-0.765**
|
p
|
0.007
|
0.621
|
0.000
|
0.473
|
0.855
|
0.000
|
0.000
|
0.021
|
0.000
|
miR-146bR
|
r
|
0.588**
|
-0.077
|
0.495**
|
0.067
|
-0.127
|
0.395*
|
0.421*
|
-0.427**
|
-0.502**
|
p
|
0.000
|
0.661
|
0.003
|
0.703
|
0.466
|
0.019
|
0.012
|
0.012
|
0.002
|
miR-15bR
|
r
|
0.388*
|
-0.019
|
0.824**
|
0.218
|
-0.102
|
0.669**
|
0.283
|
-0.583**
|
-0.355*
|
p
|
0.021
|
0.912
|
0.000
|
0.209
|
0.558
|
0.000
|
0.099
|
0.000
|
0.036
|
Betatrophin (ng/mL)
|
r
|
0.461**
|
0.077
|
0.601**
|
0.116
|
0.043
|
0.428*
|
0.458**
|
-0.410*
|
-0.425*
|
p
|
0.005
|
0.660
|
0.000
|
0.506
|
0.807
|
0.032
|
0.006
|
0.013
|
0.011
|
**Correlation is significant at the 0.01 level (2-tailed)
*Correlation is significant at the 0.05 level (2-tailed).
T2DM: type 2 diabetes mellitus, BMI: body mass index, HDLc: high density lipoprotein cholesterol, LDLc: low density lipoprotein cholesterol, HbA1c: glycated hemoglobin, TAC: triacylglycerol, microR-486R: microRNA 486 relative expression, miR-146bR: microRNA 146b relative expression, miR-15bR: microRNA 15b relative expression.
The efficacy of circulating microRNAs 486, 146b and 15b relative expressions and serum betatrophin levels in differentiating non-diabetic obese children from obese children with T2DM is illustrated in figure 3. The areas under ROC were 0.61, 0.54, 0.62 and 0.59, respectively.