The effects of grape seed on apoptosis-related gene expression and oxidative stress in streptozotocin-induced diabetic rats

Figures & data

Table 1. Extraction properties of the freeze-dried GSEs and the efficiency of the extraction procedure.

Property	Value (%)
Total phenolic content (gallic acid equivalent)	45.1
Total flavonoid content (catechin equivalent)	27.1
Extraction efficiency	1.12

Table 2. Phenolic content (on a dry matter basis) and antioxidant activity (FRAP method) of grape seeds obtained from the wastes of grape molasses production.

Property	Value
Total phenolic content (mg GAE/g)	54.6 ± 6.4
Antioxidant activity (mmol Trolox Equivalent/g)	36.2 ± 5.5

Table 3 Gallic acid, catechin and epicatechin contents of freeze-dried extracts of grape seeds.

Substance	Concentration (mg/100 g GSE)
Gallic acid	53.5 ± 5.6
Catechin	65.9 ± 9.5
Epicatechin	45.4 ± 8.7

Table 4. Experimental groups and study flowchart.

Groups	Day 0	Day 3 (serum glucose levels >300 mg/dL)	Week 8
Control group	–	–	–
Diabetic rats	STZ 60 mg/kg	+	0.5 mL saline
Grape seed treated diabetic rats	STZ 60 mg/kg	+	Grape seed extract (100 mg/kg/day, in 0.5 mL saline, oral gavage)

Figure 1. Comparison of total oxidative status (TOS) values across groups. Group 1; control group, Group 2; diabetic rats, Group 3; grape seed treated diabetic rats. *Group 2 versus Group 3; p < 0.05.

Figure 2. Comparison of total antioxidant status (TAS) values across groups. Group 1; control group, Group 2; diabetic rats, Group 3; grape seed treated diabetic rats. Group 1 versus Group 3; p: NS, Group 2 versus Group 3; p: NS.

Figure 3. Comparison of oxidative stability index (OSI) values across groups. Group 1; control group, Group 2; diabetic rats, Group 3; grape seed-treated diabetic rats. *Group 1 versus Group 3; p < 0.001. **Group 2 versus Group 3; p < 0.001.

Table 5. Comparison of gene expression of all groups with the control group.

Gene name	Diabetic rats p value	Grape seed-treated diabetic rats p value
CASP1	0.028*	0.021*
IL1-ALPHA	0.046*	0.055
CASP2	0.389	0.023*
IL1-BETA	0.272	0.051
BAD	0.002*	0.233
XIAP	0.147	0.003*
DFFA	0.006*	<0.0001*
DFFB	0.005*	0.917
BID	0.750	0.018*
CASP6	0.042*	0.959
BCL-XL	0.541	0.040*
CASP8	0.505	0.050*
TNFRSF1B	0.414	0.025*
DIABLO	0.045*	0.063

Notes: *p < 0.05. Caspase 1 (CASP1), interleukin 1 alpha (IL1-alpha), caspase 2 (CASP2), interleukin 1 beta (IL1-beta), BCL2-associated agonist of cell death (BAD), X-linked inhibitor of apoptosis (XIAP), DNA fragmentation factor, alpha subunit (DFFA), DNA fragmentation factor, beta polypeptide (caspase-activated DNase) (DFFB), BH3 interacting domain death agonist (BID), caspase 6 (CASP6), Bcl2-like 1 (BCL-XL), caspase 8 (CASP8), tumor necrosis factor receptor superfamily member 1 B (TNFRSF1B) and Diablo IAP-binding mitochondrial protein (DIABLO).

Table 6. Comparison of gene expression of grape seed group with the diabetic group.

Gene name	p Value
BAD	0.001*
DFFA	0.001*
DFFB	0.001*
CASP6	0.003*
DIABLO	0.004*

Notes: *p < 0.05. BCL2-associated agonist of cell death (BAD), DNA fragmentation factor, alpha subunit (DFFA), DNA fragmentation factor, beta polypeptide (caspase-activated DNase) (DFFB), caspase 6 (CASP6), Diablo IAP-binding mitochondrial protein (DIABLO).