Beta-sitosterol improves cerebral ischemia-reperfusion injury in rats by inhibiting endoplasmic reticulum stress
10.3760/cma.j.cn115354-20240810-00474
- VernacularTitle:β-谷甾醇通过抑制内质网应激改善大鼠脑缺血再灌注损伤
- Author:
Xingyun YUAN
1
;
Fei WANG
;
Wanhong CHEN
;
Wenqiang LI
;
Juanli ZHANG
;
Qing LIU
;
Jialun XIN
;
Li YAO
Author Information
1. 咸阳市第一人民医院神经内科，咸阳 712000
- Keywords:
Cerebral ischemia-reperfusion injury;
β-sitosterol;
Endoplasmic reticulum stress
- From:
Chinese Journal of Neuromedicine
2024;23(9):886-894
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To reveal the effect of β-sitosterol on cerebral ischemia-reperfusion injury (CIRI) in rats and whether its mechanism is related to endoplasmic reticulum stress (ERS).Methods:Fifty-three CIRI rats (CIRI models established by modified Longa method) were randomly divided into model group ( n=14), β-sitosterol low-dose group ( n=13), β-sitosterol medium-dose group ( n=13) and β-sitosterol high-dose group ( n=13); 12 rats underwent the same operation without blocking the middle cerebral artery were selected as sham-operated group. Rats in the sham-operated group and model group were given intragastric administration of 1 mL 5 g/L sodium carboxymethyl cellulose daily. Rats in the β-sitosterol low-dose group, β-sitosterol medium-dose group and β-sitosterol high-dose group were given intragastric administration of 1 mL β-sitosterol at 10, 20 and 40 mg/kg/d (dissolved in 5 g/L sodium carboxymethyl cellulose), respectively, for 14 consecutive d. Neurological function was evaluated according to Zea Longa 5 method. Rats were sacrificed and brain tissues were collected. Volume of cerebral infarction was measured by 2,3,5-triphenyl tetrazolium chloride (TTC) staining. Brain injury and neuronal apoptosis were evaluated by HE staining, Nissl staining and TUNEL. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) contents were detected by water-soluble tetrazolium 1 (WST-1) method, colorimetric method or thiobarbituric acid (TBA) method, respectively. The mRNA and protein expression levels of protein kinase R-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme-1 (IRE-1), activated transcription factor-6 (ATF-6), glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP) and Caspase-12 in the brain tissues were detected by qRT-PCR or Western blotting. Results:Compared with the sham-operated group, the model group had significantly increased neurological function score, cerebral infarction volume and TUNEL positive rate, decreased SOD and GSH-Px content, increased MDA content, and increased mRNA and protein expressions of PERK, IRE-1, ATF-6, GRP78, CHOP and Caspase-12 ( P<0.05). Compared with the model group, the β-sitosterol low-dose group, β-sitosterol medium-dose group and β-sitosterol high-dose group had significantly decreased neurological function score, cerebral infarction volume, and TUNEL positive rate, increased SOD and GSH-Px content, and decreased MDA content ( P<0.05); the β-sitosterol low-dose group, β-sitosterol medium-dose group and β-sitosterol high-dose group had significantly decreased mRNA and protein PERK expressions (mRNA: 2.17±0.17, 1.79±0.07 and 1.33±0.07; protein: 5.11±0.52, 2.91±0.26 and 1.98±0.17), IRE-1 expressions (mRNA: 1.75±0.18, 1.65±0.08 and 1.32±0.08; protein: 5.00±0.31, 4.05±0.27 and 1.98±0.14), ATF-6 expressions (mRNA: 2.24±0.12, 1.77±0.14 and 1.37±0.13; protein: 4.93±0.45, 4.04±0.30 and 3.10±0.20), GRP78 expressions (mRNA: 2.67±0.16, 2.11±0.16 and 1.69±0.11; protein: 5.02±0.38, 2.97±0.26 and 2.05±0.22), CHOP expressions (mRNA: 2.01±0.16, 1.70±0.19 and 1.40±0.10; protein: 4.92±0.39, 4.02±0.27 and 3.08±0.22) and Caspase-12 expressions (mRNA: 1.85±0.09, 1.61±0.09 and 1.30±0.09; protein: 3.03±0.20, 2.19±0.11 and 1.82±0.11) compared with the model group (mRNA: 2.99±0.28, 2.27±0.12, 2.57±0.21, 3.46±0.20, 2.50±0.23 and 2.35±0.16; protein: 6.98±0.48, 6.03±0.58, 5.98±0.63, 7.10±0.45, 6.00±0.53 and 5.02±0.43, P<0.05). Conclusion:β-sitosterol attenuates CIRI in rats, whose mechanism may be related to inhibition of ERS signal pathway.
