Galangin, a dietary flavonoid, improves antioxidant status and reduces hyperglycemia-mediated oxidative stress in streptozotocin-induced diabetic rats

Figures & data

Figure 1. Chemical structure of galangin.

Table 1. Effect of galangin on plasma glucose and insulin in STZ-diabetic rats.

Groups	Glucose (mg/dl)	Insulin (μU/ml)
Control	89.93 ± 4.74^a	15.62 ± 1.10^a
Control + galangin (16 mg/kg BW)	85.11 ± 4.94^a	15.77 ± 0.91^a
Diabetic control	281.10 ± 9.57^b	6.01 ± 0.44^b
Diabetic + galangin (4 mg/kg BW)	179.86 ± 0.86^c	8.14 ± 0.79^c
Diabetic + galangin (8 mg/kg BW)	117.10 ± 11.32^d	12.08 ± 1.04^d
Diabetic + galangin (16 mg/kg BW)	140.53 ± 7.24^e	10.45 ± 1.72^e
Diabetic + glibenclamide (600 μg/kg BW)	99.49 ± 5.18^f	14.20 ± 1.55^f

Values are given as means ± S.D. for six rats in each group.

^a,b,c,d,e,fValues not sharing a common superscript differ significantly at P < 0.05. Duncan’s Multiple Range Test (DMRT).

Figure 2. Effect of galangin on TBARS in the plasma and tissues of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 are significantly different from group 3 (b vs. c, a, d) (P < 0.05).

Figure 3. Effect of galangin on LOOH (LOOH) in the plasma and tissues of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 are significantly different from group 3 (b vs. c, ac, d) (P < 0.05).

Figure 4. Effect of galangin on CD in the plasma and tissues of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 significantly are different from group 3 (b vs. c, ac, d) (P < 0.05).

Figure 5. Effect of galangin on the activity of SOD in the liver and kidney of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 are significantly different from group 3 (b vs. c, ac) (P < 0.05). U* = Enzyme concentration required for 50% inhibition of NBT reduction/minute.

Figure 6. Effect of galangin on the activity of catalase (CAT) in the liver and kidney of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 are significantly different from group 3 (b vs. d, e, c) (P < 0.05). U* = µmol of hydrogen peroxide consumed/minute.

Figure 7. Effect of galangin on the activity of GPx in the liver and kidney of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 are significantly different from group 3 (b vs. c, a, c) (P < 0.05). U* = µmol of GSH utilized/minute.

Figure 8. Effect of galangin on the activity of GST in the liver and kidney of normal and STZ-induced diabetic rats. Values are given as means ± SD from six rats in each group. Group 1 is significantly not different from group 2 (a, a) (P < 0.05). Group 4 and 5 are significantly different from group 3 (b vs. c, a) (P < 0.05). U* = µg of CDNB conjugate formed/minute.

Table 2. Effect of galangin on vitamin C in the plasma and tissues of normal and STZ-induced diabetic rats.

Groups	Plasma vitamin C (mg/dl)	Tissue vitamin C (µg/mg protein)
		Liver	Kidney
Control	2.09 ± 0.15^a	0.85 ± 0.06^a	0.76 ± 0.05^a
Control + galangin (8 mg/kg BW)	2.15 ± 0.19^a	0.87 ± 0.07^a	0.78 ± 0.06^a
Diabetic control	0.79 ± 0.06^b	0.40 ± 0.02^b	0.60 ± 0.05^b
Diabetic + galangin (8 mg/kg BW)	1.66 ± 0.13^c	0.79 ± 0.06^c	0.81 ± 0.07^c
Diabetic + glibenclamide (600 µg/kg BW)	1.81 ± 0.10^d	0.81 ± 0.05^a	0.80 ± 0.06^c

Values are given as means ± SD from six rats in each group.

^a,b,c,dValues not sharing a common superscript differ significantly at P < 0.05. DMRT.

Table 3. Effect of galangin on vitamin E in the plasma and tissues of normal and STZ-induced diabetic rats.

Groups	Plasma vitamin E (mg/dl)	Tissue vitamin E (µg/mg protein)
		Liver	Kidney
Control	1.93 ± 0.13^a	5.34 ± 0.41^a	3.51 ± 0.18^a
Control + galangin (8 g/kg BW)	1.79 ± 0.11^b	5.22 ± 0.30^a	3.57 ± 0.20^a
Diabetic control	0.68 ± 0.04^c	3.41 ± 0.22^b	1.39 ± 0.09^b
Diabetic + galangin (8 mg/kg BW)	1.23 ± 0.10^d	4.01 ± 0.34^c	2.68 ± 0.14^c
Diabetic + glibenclamide (600 µg /kg BW)	1.45 ± 0.12^e	4.56 ± 0.38^d	3.06 ± 0.28^d

Values are given as means ± SD from six rats in each group.

^a,b,c,d,eValues not sharing a common superscript differ significantly at P < 0.05. DMRT.

Table 4. Effect of galangin on reduced glutathione in the plasma and tissues of normal and STZ-induced diabetic rats.

Groups	Plasma GSH (mg/dl)	Tissue GSH (µg/mg protein)
		Liver	Kidney
Control	28.86 ± 1.78^a	14.25 ± 1.20^a	9.55 ± 0.74^a
Control + galangin (8 mg/kg BW)	33.04 ± 2.85^a	14.92 ± 1.34^a	9.97 ± 1.62^a
Diabetic control	16.65 ± 1.33^b	5.06 ± 0.36^b	4.82 ± 0.30^b
Diabetic + galangin (8 mg/kg BW)	23.98 ± 1.56^c	12.08 ± 1.0^c	8.18 ± 0.60^c
Diabetic + glibenclamide (600 µg/kg BW)	27.42 ± 2.64^a,c	13.64 ± 1.28^a	8.89 ± 0.57^c

Values are given as means ± S.D. from six rats in each group.

^a,b,cValues not sharing a common superscript differ significantly at P < 0.05. DMRT.