The demographic and clinical parameters extracted from the study participants via questionnaire and their recent medical history are included in this study are presented in Table 2.
Table 2: Biochemical and demographic characteristics of study participants under different groups.
Characteristics
|
Control (N=100)
|
T2DM without DN (N=100)
|
T2DM with DN (N=100)
|
p value
|
Gender
|
52/48
|
56/44
|
69/31
|
0.03*
|
Age
|
58.2 ± 5.9
|
57.5 ± 6.8
|
59.1 ± 7.2
|
0.9
|
BMI
|
24.0 ± 4.0
|
24.1 ± 3.4
|
24.0 ± 3.6
|
0.9
|
Diabetes duration
|
|
|
|
|
2-5 years
|
˗
|
38
|
34
|
˗
|
5-10 years
|
˗
|
62 (15.5 ± 5.7)
|
66 (16.5 ± 6.5)
|
0.9
|
FBG
|
84.5 ± 8.7
|
184 ± 66.7
|
181.6 ± 63.7
|
0.001*
|
PPG
|
115.6 ± 12.1
|
258.8 ± 93.5
|
257.5 ± 91.6
|
<0.002*
|
HbA1c
|
7.6 ± 1.8
|
9.1 ± 2.2
|
9.1 ± 2.2
|
0.9
|
ACR
|
31.4 ± 1.13
|
52.3 ± 2.3
|
60.8 ± 5.4
|
0.5
|
Creatinine
|
0.70 ± 0.12
|
0.75 ± 0.15
|
20.7 ±133.5
|
0.002*
|
BUN
|
11.2 ± 3.8
|
13.4 ± 4.1
|
56 ± 14.1
|
<0.01*
|
HDL
|
47 ± 15.5
|
60 ± 18.01
|
62.1 ± 15.5
|
0.78
|
LDL
|
92.5 ± 30
|
95 ± 30.1
|
97.4 ± 29.4
|
0.97
|
eGFR
|
130.6 ± 15.8
|
102.1 ± 12.5
|
46.8 ± 17.2
|
<0.01*
|
SBP
|
112 ± 7.2
|
134.08 ± 6.9
|
143.7 ± 5.3
|
<0.01*
|
DBP
|
73.2 ± 5.2
|
89 ± 5.0
|
106.9 ± 5.2
|
<0.01*
|
MDA
|
1.14 ± 0.26
|
2.89 ± 0.53
|
4.76 ± 0.66
|
< 0.001*
|
TAS
|
1.25 ± 0.17
|
0.43 ± 0.09
|
0.32 ± 0.07
|
< 0.001*
|
SOD
|
6.14 ± 0.88
|
3.06 ± 0.67
|
2.70 ± 0.40
|
< 0.001*
|
CAT
|
7.27 ± 0.75
|
3.43 ± 0.61
|
3.09 ± 0.69
|
< 0.001*
|
GPx
|
6.89 ± 0.98
|
3.56 ± 0.76
|
2.97 ± 0.57
|
< 0.001*
|
T2DM: Type 2 diabetes mellitus, DN: Diabetic nephropathy, * indicates statistically significant p<0.05
This table represents the biochemical and clinical characteristics of the study participants from all the three distinct groups considered in this research. The majority of population participated in the study were males. Furthermore, male participants are likely-significant to develop T2DM with nephropathy, as manifested by the OR 1.453 (1.060-1.993), p=0.02. The study participants comprising of 59% of males and 41% of females influence a mean age of 58.0±6.6 and the mean BMI of 24.0±3.7. Patients with T2DM associated nephropathy were found to have significantly (p<0.05) greater levels of FBG, PPBG, serum creatinine, BUN, SBP, and DBP when compared to the controls. On the other hand, eGFR levels are depicted to be decreased in the T2DM associated nephropathy group in comparison with the other two groups (p<0.05). Regression analysis discloses that increased PPBG levels indicate the high-outrage of thriving oxidative stress mediated T2DM and DN pathogenesis. Group 2 and 3 had significantly greater levels of MDA and lower TAS levels in comparison with the controls. T2DM with nephropathy patients had the truncated extents of antioxidants (specifically SOD, CAT, and GPx) and the overhead levels of lipid peroxidation, insinuating that oxidative damage upraise the risk of DN in hyperglycemic conditions.
Table 3 depicts the genotypic frequency of MnSOD (rs4880), CAT (rs1049982), and GPx1 (rs1050450) of the study participants from three different groups considered for this research. Primarily, MnSOD (rs4880) AA and CAT (rs1049982) AA genotype was prevalently common in T2DM without DN and T2DM with DN groups compared to the controls but does not statistically significant difference. Next, GPx1 (rs1050450) AA genotype was observed to be more prevalent in T2DM with and without DN groups in comparison with control group. Subsequently, GPx1 (rs1050450) GA genotype was predicted in T2DM with DN group whereas the other groups do not show any heterozygous genotype. GPx1 (rs1050450) dominant, recessive and heterozygous genotype have shown statistically significant difference (p<0.05) between the three study groups.
Table 3: Genotypic frequencies of MnSOD, CAT, and GPx1 in different groups.
Genes/Genotypes
|
Control (N=100)
|
T2DM without DN (N=100)
|
T2DM with DN (N=100)
|
Association (df=2)
|
P-value
|
MnSOD (rs4880)
|
1.787
|
0.41
|
AA
|
45
|
54
|
52
|
TT
|
55
|
46
|
48
|
CAT (rs1049982)
|
0.562
|
0.75
|
AA
|
63
|
66
|
68
|
TT
|
37
|
34
|
32
|
GPx1 (rs1050450)
|
10.78
|
0.03*
|
AA
|
48
|
57
|
65
|
GG
|
52
|
43
|
33
|
GA
|
0
|
0
|
2
|
T2DM: Type 2 diabetes mellitus, DN: Diabetic nephropathy, * indicates statistically significant p<0.05
Table 3 represents that homozygous dominant genotype (AA) of MnSOD, CAT, and GPx1 was significantly greater in Group 2 and 3 when compared to the controls and was analogous in developing T2DM and DN progression. Moreover, on comparison between the T2DM without DN and with DN group: rs4880 (AA) genotype of T2DM without DN (OR: 1.43 [0.82-2.50] p=0.20) and with DN (OR: 0.92 [0.53-1.61] p=0.77), rs1049982 (AA) genotype of T2DM without DN (OR: 1.14 [0.64-2.04] p=0.66) and with DN (OR: 1.09 [0.61-1.97] p=0.76), and rs1050450 (AA) genotype in T2DM without DN (OR: 1.44 [0.82-2.50] p=0.20) and with DN (OR: 1.49 [0.84-2.64] 0.18) respectively was not significantly associated with the risk of developing DN in T2DM patients. A history of prolonged duration of T2DM significantly increased the outrage of DN progression among participants included in T2DM without DN group (OR: 1.30 [0.65-2.24] p=0.01*).
Compared to AA genotype of rs4880 and rs1049982, homozygous recessive (TT) genotype had significantly higher FBG (192.5 ± 80.54), and PPG (340.6 ± 112), whereas rs4880 AA genotype showed significantly increased creatinine (25.5 ± 75.6), rs1049982 TT genotype showed significantly greater BUN (46.3 ± 2.7), and finally rs1050450 GG genotype depicted significantly higher eGFR (56.4 ± 14.3). Additionally, the antioxidant parameters exhibit highly significant difference between rs4880 AA and TT genotype, rs1050450 AA and GG genotype, no significant difference between rs1049982 AA and TT genotype.
Table 4: Risk association of rs4880, rs1049982, and rs1050450 polymorphism in different groups. Group 1: Controls, Group 2: T2DM without DN, Group 3: T2DM with DN.
SNP
|
Genetic models
|
Group 3 vs Group 1
|
Group 2 vs Group 1
|
Group 3 vs Group 2
|
OR (95% CI)/P value
|
OR (95% CI)/P value
|
OR (95% CI)/P value
|
rs4880
|
Co-dominant
|
1.324 (0.759 - 2.309) 0.322
|
1.435 (0.822 - 2.504) 0.204
|
0.923 (0.529 - 1.608) 0.780
|
rs1049982
|
Co-dominant
|
1.248 (0.696 - 2.238) 0.457
|
1.140 (0.638 - 2.035) 0.658
|
1.095 (0.607 - 1.974) 0.763
|
rs1050450
|
Co-dominant
|
2.134 (1.202 - 3.788) 0.009*
|
1.436 (0.823 - 2.507) 0.203
|
1.486 (0.835 - 2.644) 0.178
|
Dominant
|
2.015 (1.117 - 3.634) 0.02*
|
-
|
1.532 (0.862 - 2.722) 0.146
|
Recessive
|
2.215 (1.235 - 3.972) 0.008*
|
-
|
1.401 (0.792 - 2.479) 0.247
|
T2DM: Type 2 diabetes mellitus, DN: Diabetic nephropathy, * indicates statistically significant p<0.05
Table 4 displayed the risk association of rs4880, rs1049982, and rs1050450 polymorphism in T2DM with DN and controls, T2DM without DN and controls, finally T2DM with DN and without DN. This table represents all the models of rs1050450 genotype showing positive association in T2DM patients with DN and controls exhibiting a p value <0.05, whereas a negative association was observed in T2DM patients without DN and controls, and also between T2DM with- and without DN patients showing a p value >0.05 among all the genetic models. Moreover, Table 4 reveals that the analysis of rs4880, and rs1049982 manifest negative association (p>0.05) between the study groups with respect to all the genetic models.
Table 5: The relation between plasma MDA, TAS, antioxidant parameters and rs4880, rs1049982, and rs1050450 genotypes in different groups.
S.No.
|
Parameter/SNP
|
Genotypes
|
Control N=100
|
P value
|
T2DM without DN N=100
|
P value
|
T2DM with DN N=100
|
P value
|
|
|
1
|
MDA/rs4880
|
AA
|
1.08 ± 0.20
|
0.37
|
1.30 ± 0.29
|
0.75
|
2.76 ± 0.50
|
0.01
|
|
TT
|
1.12 ± 0.24
|
1.32 ± 0.34
|
3.02 ± 0.54
|
|
2
|
MDA/rs1049982
|
AA
|
1.14 ± 0.22
|
<0.001
|
2.34 ± 0.26
|
0.09
|
3.54 ± 0.52
|
<0.01
|
|
TT
|
1.32 ±0.30
|
2.45 ± 0.39
|
2.12 ± 0.24
|
|
3
|
MDA/rs1050450
|
AA
|
1.24 ± 0.16
|
<0.02
|
2.54 ± 0.42
|
<0.001
|
4.02 ± 0.56
|
<0.001
|
|
GG
|
1.02 ± 0.10
|
2.12 ± 0.34
|
2.01 ± 0.32
|
|
4
|
TAS/rs4880
|
AA
|
1.2 ± 0.12
|
0.15
|
0.32 ± 0.07
|
<0.01
|
0.17 ± 0.02
|
<0.01
|
|
TT
|
1.24 ± 0.15
|
0.40 ± 0.05
|
0.19 ± 0.05
|
|
5
|
TAS/rs1049982
|
AA
|
1.17 ± 0.17
|
<0.01
|
0.39 ± 0.05
|
<0.001
|
0.35 ± 0.12
|
<0.01
|
|
TT
|
0.12 ± 0.02
|
0.45 ± 0.09
|
0.15 ± 0.01
|
|
6
|
TAS/rs1050450
|
AA
|
1.07 ± 0.21
|
0.1
|
0.27 ± 0.09
|
<0.01
|
0.19 ± 0.02
|
<0.01
|
|
GG
|
0.36 ± 0.03
|
0.36 ± 0.03
|
0.31 ± 0.07
|
|
7
|
SOD/rs4880
|
AA
|
4.78 ± 0.75
|
<0.01
|
2.07 ± 0.54
|
<0.01
|
1.95 ± 0.25
|
<0.01
|
|
TT
|
5.45 ± 0.69
|
3.15 ± 0.25
|
2.65 ± 0.37
|
|
8
|
SOD/rs1049982
|
AA
|
5.94 ± 0.67
|
0.02
|
2.71 ± 0.51
|
0.02
|
1.49 ± 0.35
|
<0.001
|
|
TT
|
2.10 ± 0.25
|
2.93 ± 0.29
|
2.95 ± 0.21
|
|
9
|
SOD/rs1050450
|
AA
|
4.82 ± 0.50
|
0.001
|
2.75 ± 0.59
|
<0.01
|
1.73 ± 0.24
|
<0.001
|
|
GG
|
3.74 ± 0.28
|
1.36 ± 0.08
|
2.32 ± 0.35
|
|
10
|
CAT/rs4880
|
AA
|
5.29 ± 0.49
|
<0.0001
|
1.59 ± 0.56
|
<0.0001
|
2.09 ± 0.32
|
<0.001
|
|
TT
|
3.72 ± 0.45
|
2.86 ± 0.43
|
1.94 ± 0.38
|
|
11
|
CAT/rs1049982
|
AA
|
6.01 ± 0.62
|
<0.0001
|
1.89 ± 0.35
|
<0.0001
|
2.17 ± 0.42
|
<0.01
|
|
TT
|
1.29 ± 0.20
|
2.64 ± 0.42
|
1.62 ± 0.33
|
|
12
|
CAT/rs1050450
|
AA
|
4.32 ± 0.51
|
<0.0001
|
1.43 ± 0.39
|
<0.0001
|
3.21 ± 0.55
|
<0.01
|
|
GG
|
3.69 ± 0.25
|
2.49 ± 0.26
|
2.15 ± 0.32
|
|
13
|
GPx1/rs4880
|
AA
|
4.65 ± 0.72
|
0.001
|
2.01 ± 0.50
|
0.0001
|
1.65 ± 0.20
|
<0.0001
|
|
TT
|
5.40 ± 0.65
|
2.98 ± 0.26
|
2.54 ± 0.29
|
|
14
|
GPx1/rs1049982
|
AA
|
4.94 ± 0.62
|
0.01
|
2.42 ± 0.39
|
<0.001
|
1.45 ± 0.31
|
<0.001
|
|
TT
|
2.45 ± 0.19
|
2.76 ± 0.21
|
2.72 ± 0.18
|
|
15
|
GPx1/rs1050450
|
AA
|
4.45 ± 0.70
|
0.01
|
2.49 ± 0.31
|
<0.01
|
1.39 ± 0.27
|
<0.001
|
|
GG
|
5.01 ± 0.31
|
2.61 ± 0.18
|
2.15 ± 0.17
|
|
T2DM: Type 2 diabetes mellitus, DN: Diabetic nephropathy * indicates statistically significant p<0.05
The relationship between rs4880, rs1049982, rs1050450 genotypes and antioxidant parameters are illustrated in Table 5. This table shows significant association of all genotypes corresponding to rs4880, rs1049982, rs1050450 and antioxidant parameters (MDA, TAS, SOD, CAT, and GPx) with few exceptions such as: Lipid peroxidation of MnSOD genotypes in T2DM patients and controls does not differ significantly (p>0.05); Plasma TAS level was not significant (p>0.05) between the genotypes of MnSOD among the controls; Thereafter, lipid peroxidation of CAT genotypes were insignificant (p>0.05) in T2DM patients compared to other groups; Subsequently, plasma TAS level of GPx1 genotypes does not show significant association in controls. These results suggest that the rs4880 and rs1049982 on comparison with rs1050450 variants could not influence DN progression in T2DM patients.