Protective effect of sericin on streptozotocin-induced INS-1 cell damage by regulating PI3K/Akt/NF-κB signaling pathway through Akt1 and its mechanism
10.13481/j.1671-587X.20250304
- VernacularTitle:丝胶通过Akt1调控PI3K/Akt/NF-κB信号通路对链脲佐菌素引起INS-1细胞损伤的保护作用及其机制
- Author:
Cheng CHEN
1
;
Jingyao LI
;
Wanxiang HU
;
Donghui LIU
;
Zhihong CHEN
Author Information
1. 承德医学院基础医学院生理学教研室,河北 承德 067000
- Keywords:
Sericin;
INS-1 cells;
Phosphatidylinositol 3-kinase/protein kinase B/nuclear factor-κB signaling pathway;
Inflammatory response;
Apoptosis
- From:
Journal of Jilin University(Medicine Edition)
2025;51(3):590-598
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To discuss the effect of sericin on the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/nuclear factor-κB(NF-κB)signaling pathway and apoptosis in the streptozotocin(STZ)-damaged INS-1 cells,and to clarify its mechanism.Methods:The INS-1 cells were cultured with complete medium containing 0,0.1,0.3,1.0,3.0,and 10.0 μmol·L-1 Akt1 inhibitor A-674563,10 mmol·L-1 STZ,and 600 mg·L-1 sericin,and divided into 0,0.1,0.3,1.0,3.0,and 10.0 μmol·L-1 A-674563 groups,and the control group(complete medium without drugs)was set up.Cell counting kit-8(CCK-8)method was used to detect the survival rates of the INS-1 cells,and the half-maximal inhibitory concentration(IC50)value was calculated to determine the optimal inhibitory concentration of A-674563,which was further verified by Western blotting method.The INS-1 cells were divided into normal control group(complete medium),model group(10 mmol·L-1 STZ+complete medium),and low,medium,and high doses of sericin groups(10 mmol·L-1 STZ+150 mg·L-1 sericin+complete medium,10 mmol·L-1 STZ+300 mg·L-1 sericin+complete medium,and 10 mmol·L-1 STZ+600 mg·L-1 sericin+complete medium).CCK-8 method was used to detect the survival rates of the INS-1 cells in various groups to determine the optimal concentration of sericin.Additionally,the INS-1 cells were divided into normal control group(complete medium),model group(10 mmol·L-1 STZ+complete medium),sericin group(10 mmol·L-1 STZ+600 mg·L-1 sericin+complete medium),and A-674563 group(10 mmol·L-1 STZ+600 mg·L-1 sericin+0.3 μmol·L-1 A-674563+complete medium).Flow cytometry was used to detect the apoptotic rates of the INS-1 cells in various groups;real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression levels of Akt1,NF-κB,tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)mRNA in the INS-1 cells in various groups;Western blotting method was used to detect the expression levels of phosphorylated Akt1(p-Akt1)and NF-κB proteins in the INS-1 cells in various groups;enzyme linked immunosorbent assay(ELISA)method was used to detect the levels of TNF-α and IL-6 in the INS-1 cells in various groups.Results:The survival rates of the INS-1 cells in control group was 100.00%±0.00%;in 0,0.1,0.3,1.0,3.0,and 10.0 μmol·L-1 A-674563+10 mmol·L-1 STZ+600 mg·L-1 sericin+complete medium groups,which were 82.50%±2.28%,69.47%±1.94%,51.51%±1.74%,38.94%±1.57%,24.79%±1.14%,and 19.85%±1.03%,respectively.The IC?? value of A-674563 for INS-1 cells was 0.3 μmol·L-1,and 0.3 μmol·L-1 A-674563 was selected for subsequent experiments.Compared with 0 μmol·L-1 A-674563,the expression level of p-Akt1 protein in the INS-1 cells after treated with 0.3 μmol·L-1 A-674563+10 mmol·L-1 STZ+600 mg·L-1 sericin+complete medium was significantly decreased(P<0.05).The CCK-8 results showed that compared with normal control group,the survival rate of the INS-1 cells in model group was significantly decreased(P<0.05);compared with model group,the survival rates of the INS-1 cells in low,medium,and high doses of sericin groups were significantly increased(P<0.05);compared with low and medium doses of sericin groups,the survival rate of the INS-1 cells in high dose of sericin group was significantly increased(P<0.05).Thus,600 mg·L-1 sericin was selected for subsequent experiments.The CCK-8 results showed that compared with normal control group,the survival rate of the INS-1 cells in model group was significantly decreased(P<0.05);compared with model group,the survival rate of the INS-1 cells in sericin group was significantly increased(P<0.05);compared with sericin group,the survival rate of the INS-1 cells in A-674563 group was significantly decreased(P<0.05).The flow cytometry results showed that compared with normal control group,the apoptotic rate of the INS-1 cells in model group was significantly increased(P<0.05);compared with model group,the apoptotic rate of the INS-1 cells in sericin group was significantly decreased(P<0.05);compared with sericin group,the apoptotic rate of the INS-1 cells in A-674563 group was significantly increased(P<0.05).The RT-qPCR results showed that compared with normal control group,the expression level of Akt1 mRNA in the INS-1 cells in model group was significantly decreased(P<0.05);compared with model group,the expression levels of Akt1 mRNA in the INS-1 cells in low,medium,and high doses of sericin groups were significantly increased(P<0.05);compared with low and medium doses of sericin groups,the expression level of Akt1 mRNA in the INS-1 cells in high dose of sericin group was significantly increased(P<0.05).Compared with normal control group,the expression levels of NF-κB,TNF-α,and IL-6 mRNA in the INS-1 cells in model group were significantly increased(P<0.05);compared with model group,the expression levels of NF-κB,TNF-α,and IL-6 mRNA in the INS-1 cells in sericin group were significantly decreased(P<0.05);compared with sericin group,the expression level of NF-κB mRNA in the INS-1 cells in A-674563 group was significantly increased(P<0.05).The Western blotting results showed that compared with normal control group,the expression level of p-Akt1 protein in the INS-1 cells in model group was significantly decreased(P<0.05);compared with model group,the expression levels of p-Akt1 protein in the INS-1 cells in low,medium,and high doses of sericin groups were significantly increased(P<0.05);compared with low and medium doses of sericin groups,the expression level of p-Akt1 protein in the INS-1 cells in high dose of sericin group was significantly increased(P<0.05).Compared with normal control group,the expression level of NF-κB protein in the INS-1 cells in model group was significantly increased(P<0.05);compared with model group,the expression level of NF-κB protein in the INS-1 cells in sericin group was significantly decreased(P<0.05);compared with sericin group,the expression level of NF-κB protein in the INS-1 cells in A-674563 group was significantly increased(P<0.05).The ELISA results showed that compared with normal control group,the levels of TNF-α and IL-6 in the INS-1 cells in model group were significantly increased(P<0.05);compared with model group,the levels of TNF-α and IL-6 in the INS-1 cells in sericin group were significantly decreased(P<0.05);compared with sericin group,the levels of TNF-α and IL-6 in the INS-1 cells in A-674563 group were significantly increased(P<0.05).Conclusion:Sericin alleviates the PI3K/Akt/NF-κB signaling pathway-mediated inflammatory response and apoptosis by targeting Akt1,exerting a protective effect against STZ-induced damage in INS-1 cells.
