Effects of BPF on biochemical parameters:
Plasma glucose level:
The present data indicated that the STZ diabetic group (G2) showed a highly significant increase (P<0.001) in plasma glucose levels compared to the normal value. No significant difference in plasma glucose levels was observed in the BPF-treated group (G3), while, the cotreated groups (G4 and G5) showed a highly significant increase in glucose levels compared to the control group (G1). In comparison with the STZ diabetic group (G2), the results indicated that the cotreated groups (G4) and (G5) showed a highly significant improvement in the level of glucose. These data are presented in Table 1 and Fig. 2.
Plasma ALT and AST levels:
The results are presented in Table 2 and Figures 3A & B demonstrated that the STZ diabetic group (G2) showed a highly significant increase (P<0.001) in plasma ALT and AST levels compared to the normal control group (G1). In the BPF group (G3) and cotreated groups (G4 and G5), the results revealed a highly significant increase and decrease (P<0.001) in ALT and AST levels compared to the (G1) and (G2) groups, respectively. The cotreated groups (G4, G5) exhibited highly significant improvements in both ALT and AST compared to STZ-injected animals (G2).
The present data demonstrated that there was no significant change in plasma glucose level in the BPF-treated group (G3), while, both the pretreatment and post-treated (G4, G5) groups had a highly significant decrease in the level of serum glucose compared to the STZ-injected rats (G2). The results showed that the activities of ALT and AST were significantly elevated in the positive control (G2) compared to the (G1) group (P<0.001). AST levels were higher than ALT levels for all animal groups.
Apelin and resistin gene expression:
Resistin gene expression showed significant changes in all studied groups when normalized Ct values were compared to the 18S rRNA (a ribosomal protein), whereas apelin gene expression showed no significant changes (Table 3 & Fig. 4). An increase in resistin gene expression was detected in the diabetic STZ-treated (G2) group compared to the non-diabetic control (G1) group (ΔCt, P < 0.01). Resistin expression was decreased in all BPF-injected groups, (G3), pre-treated (G4), and post-treated (G5) compared with the untreated diabetic group (ΔCt, P < 0.01) (Table 3 & Fig. 4). No significant changes were observed in the expression of apelin in the diabetic STZ-treated (G2) group, compared with all BPF-treated (G3, G4, G5) groups, and the vehicle control (G1) group, (Ct, P < 0.01).
Table 1. Effect of BPF (2.314 mg/kg b.w.) on the serum glucose level of male albino rats induced by STZ (45 mg/kg b.w.) for 30 days in different groups.
G5
|
G4
|
G3
|
G2
|
G1
|
|
Parameters
|
253.5 ab**
± 25.15
|
248.25 ab**
± 21.61
|
129.75 b**
± 9.62
|
549.5 a**
± 46.08
|
110
± 5.87
|
Mean
±SE
|
Glucose mg/dL
|
+130.45
|
+125.68
|
+17.95
|
+399.5
|
--
|
% of change (1)
|
-53.86
|
-54.82
|
-76.38
|
--
|
--
|
% of change (2)
|
There was a significant difference between G1 and the different rat groups.
*: P<0.05 Significant.
**: P<0.001 Highly Significant.
Nonsignificant (NS) P> 0.05
% of change (1) different from the normal control group (G1).
% of change (2) different from the STZ (G2) group.
a: significant difference from the control group.
b: significant difference from the STZ (G2) group.
Table 2. Effect of BPF (2.314 mg/kg b.w.) on plasma, ALT, and AST concentrations induced by STZ (45 mg/kg b.w.) for 30 days in different rat groups.
G5
|
G4
|
G3
|
G2
|
G1
|
|
Parameters
|
70 ab**
±5.5
|
57.25ab**
±4.51
|
72.25ab**
±7.25
|
125.5a**
±6.61
|
30.75
±3.42
|
Mean
±SE
|
ALT mg/dl
|
+127.64
|
+86.17
|
+134.9
|
+308.1
|
--
|
% of change (1)
|
-44.22
|
-54.38
|
-42.4
|
--
|
--
|
% of change (2)
|
102 ab**
±6.09
|
80.25 ab**
±4.02
|
94 ab**
±9.95
|
162.5 a**
±7.48
|
54
±5.81
|
Mean
±SE
|
AST mg/dl
|
+88.8
|
+48.6
|
+74.04
|
+200.9
|
--
|
% of change (1)
|
-37.2
|
-50.61
|
-42.1
|
--
|
--
|
% of change (2)
|
There was a significant difference between the control (G1) and different groups.
* = P<0.05 Significant.
** = P<0.001 Highly Significant.
Non-Significant P>0.05
% of change (1) different from the normal control group G1.
% of change (2) different from the STZ (G2) group.
a= a significant difference from the control group.
b= a significant difference from the STZ (G2) group.
Table 3. RT-qPCR data analysis of BPF on the gene expression in rats was normalized to those of 18S rRNA and relative to the negative control (G1).
Groups
|
G1
|
G2
|
G3
|
G4
|
G5
|
Apelin
|
0.35
± 0.017
|
0.41
± 0.013
|
0.33
± 0.015
|
0.36
± 0.021
|
0.38
± 0.017
|
Resistin
|
0.37
±0.019
|
0.48a*
±0.014
|
0.35b*
±0.016
|
0.40b*
±0.026
|
0.42b*
±0.020
|
Data are the means of three independent experiments, *p ≤ 0.05 considered significant. a= P < 0.05 compared with the control group (G1), b: P < 0.05 compared with the STZ-treated diabetic group (G2).
Plasma protein profile by SDS-PAGE:
The plasma protein profile by SDS-PAGE analysis followed a similar pattern of mRNA levels by RT-qPCR indicating that BPF has a broad impact and differentially modulates not only mRNA messages but also the levels of their functional proteins. The results showed that all plasma samples, whether control (G1), STZ-injected (G2), BPF (G3), or pre-and post-treated (G4, G5) had a similar protein composition (Fig. 5), namely, ankyrin (200 kDa), IgG (150 kDa), nephrine (136 kDa), IDE (112 kDa), albumin (65 kDa), prealbumin (55 kDa), CICP (43 kDa), ApoA-V (39 kDa), GAPDH (35 kDa), C-RP (28.3 kDa), leptin (17 kDa) and apelin (16 kDa).
Based on Figure 5, the intensity of the C-RP and apelin proteins in the STZ-treated (G2) group was greater than that in the nondiabetic control (G1). There was a distinct absence of ankyrin, Ig-G, GAPDH, and leptin in STZ-treated animals (G2), but they have recovered in BPF-treated (G3, G4, G5) rats with almost the same profile as the nondiabetic (G1) group. The BPF-treated group had the best plasma protein profile (G4). The albumin was not changed in either STZ-treated (G2, G4) or BPF-treated (G3, G5) rats compared to the vehicle control (G1).