1.Effect of miR-130a-3p targeting PPAR-γ on epithelial-mesenchymal transition in silica-induced pulmonary fibrosis
Xiaohui HAO ; Qian LI ; Yixuan JIN ; Qinxin ZHANG ; Yudi WANG ; Fang YANG
Journal of Environmental and Occupational Medicine 2025;42(2):188-195
Background At present, the treatment of silicosis is still limited, and no method is available to cure the disease. miRNAs are involved in the process of fibrosis at the transcriptional level by directly degrading target gene mRNA or inhibiting its translation. However, how miR-130a-3p regulates silicosis fibrosis has not been fully elucidated yet. Objective To investigate whether miR-130a-3p promotes epithelial-mesenchymal transition (EMT) by inhibiting peroxisome proliferators-activated receptors gamma (PPAR-γ), thereby pro-moting the process of silicotic fibrosis. To identify effective new targets for the treatment of silicotic fibrosis. Methods (1) Animal experiments: C57BL/6J mice were intratracheally injected with a one-time dose of 10 mg silica suspension (dissolved in 100 μL saline) as positive lung exposure. A silicosis model group was established 28 d after the exposure. A control group was injected with the same amount of normal saline into the trachea. Hematoxylin-eosin staining and Sirius red staining were used to observe the pathological changes and collagen deposition in lung tissues respectively. Realtime fluorescence-based quantitative polymerase chain reaction (RT-qPCR) was used to assay the expression of miR-130a-3p and PPAR-γ mRNA in lung tissues. Western blotting was used to detect the protein expression of PPAR-γ, transforming growth factor (TGF)-β1, E-cadherin, α-smooth muscle actin (α-SMA), and Collagen Ⅰ in lung tissues. (2) Cells experiments: Mouse lung epithelial cells (MLE-12) were induced with 5 µg·L−1 TGF-β1 for different time (0, 12, 24, 48 h). RT-qPCR was used to detect the expression of miR-130a-3p and PPAR-γ mRNA in cells. The binding relationship between miR-130a-3p and PPAR-γ mRNA was verified by dual luciferase reporter gene assay. MLE-12 cells were stimulated by 5 µg·L−1 TGF-β1 after transfection of miR-130a-3p inhibitor, and Western blotting was used to measure the protein expression of PPAR-γ, E-cadherin, and α-SMA in the TGF-β1-induced cells. Results In the silicosis model group, the alveolar septum was widened and the pulmonary nodules were formed. The Sirius red staining collagen deposition in pulmonary nodules indicated that a silicosis fibrosis model was successfully established. The expressions of TGF-β1, α-SMA, and Collagen Ⅰ proteins were increased, and the expressions of E-cadherin and PPAR-γ proteins were decreased in lung tissues of the silicosis group, compared with the control group (P<0.05 or P<0.01). The expression of miR-130a-3p was increased and the expression of PPAR-γ mRNA was decreased in lung tissues of the silicosis model (P<0.01). The expression of miR-130a-3p was significantly increased, while the expression of PPAR-γ mRNA was decreased in the TGF-β1 induced MLE-12 cells (P<0.05 or P<0.01). The dual luciferase reporter assay showed a direct relationship between miR-130a-3p and PPAR-γ mRNA in MLE-12 cells. The transfection of miR-130a-3p inhibitor in the TGF-β1 induced MLE-12 cells inhibited the decrease of PPAR-γ and E-cadherin proteins, and the increase of α-SMA protein in the MLE-12 cells induced by TGF-β1 (P<0.05 or P<0.01). Conclusion miR-130a-3p promotes the development of silicosis fibrosis by targeting PPAR-γ to increase pulmonary EMT.
2.Bugansan Regulates R-spondin1/Wnt3a-mediated Intestinal Injury to Ameliorate Digestion and Absorption Dysfunction in Rat Model of Aging Induced by D-galactose
Yixuan WANG ; Ran HUO ; Jin TIAN ; Fang FANG ; Na LIU ; Jiepeng WANG ; Chaoyi FANG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(9):19-27
ObjectiveTo elucidate the correlation between alterations in digestion and absorption functions and hepatic deficiency states in aging rats based on the R-spondin1/Wnt3a signaling pathway, and reveal the intervention mechanism of Bugansan. MethodsForty-eight SPF-grade male SD rats were randomly assigned to six groups: blank control, model, low-, medium-, and high-dose (7.03, 14.06, 28.12 g·kg-1, respectively) Bugansan, and vitamin E (suspension, 27 mg·kg-1), with 8 rats in each group. The rat model of aging was established by intraperitoneal injection of D-galactose (400 mg·kg-1), while the blank control group was injected with normal saline. Since the day of modeling, rats in intervention groups received corresponding agents by gavage, and those in blank control and model groups received an equal volume of normal saline (10 mL·kg-1). General biological features such as fur color, activity, body mass, water intake, and food intake were observed. Meanwhile, the content of malondialdehyde (MDA) and the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the serum were measured to assess aging. Grip strength and the content of total bile acids (TBA) and the activity of α-amylase (AMY) in the serum were measured to evaluate hepatic deficiency states. The activity of β-galactosidase (β-gal) in the duodenum was measured to evaluate intestinal senescence. The levels of glucagon-like peptide-1 (GLP-1), vasoactive intestinal peptide (VIP), and D-xylose in the serum were determined to assess digestion and absorption functions of the small intestine. Hematoxylin-eosin staining was conducted to observe pathological changes of the duodenum to assess the small intestine damage. Immunohistochemical staining was employed to visualize the expression of B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi1) and leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) in the duodenal tissue. Moreover, Real-time quantitative polymerase chain reaction (Real-time PCR) was utilized to quantify the mRNA levels of Ki67, Bmi1, and Lgr5 to assess proliferation and regeneration of the small intestine. Additionally, the mRNA levels of R-spondin1, Wnt3a, β-catenin, and glycogen synthase kinase-3β (GSK-3β) and the protein levels of R-spondin1, Wnt3a, β-catenin, and phosphorylated GSK-3β (p-GSK-3β) in the duodenum were determined by Real-time PCR and Western blot, respectively, to analyze the mechanisms of intestinal digestion and absorption dysfunction in aging rats and the regulatory characteristics of Bugansan. ResultsCompared with blank control group, the model group showed decreases in body mass, water intake, food intake, grip strength, activities of SOD, GSH-Px, and AMY in the serum and content of GLP-1, VIP and D-xylose in the serum (P<0.05), increases in the content of MDA and TBA in the serum and β-gal activity in the duodenum (P<0.05), reductions in villus length, villus width, crypt depth, and villi/crypt (V/C) value, down-regulated mRNA and protein levels of Ki67, Lgr5, Bmi1, R-spondin1, Wnt3a, β-catenin, and up-regulated level of GSK-3β, phosphorylation (p)-GSK-3β (P<0.05). Compared with the model group, Bugansan increased the body mass, water intake, food intake, grip strength, and activities of SOD, GSH-Px, and AMY and levels of GLP-1, VIP and D-xylose in the serum (P<0.05), while decreasing the content of MDA and TBA in the serum and β-gal activity in the duodenum (P<0.05). Furthermore, Bugansan increased the villus length, villus width, crypt depth, and V/C value, up-regulated the mRNA and protein levels of Ki67, Lgr5, Bmi1, R-spondin1, Wnt3a, β-catenin, and down-regulated the level of GSK-3β and p-GSK-3β (P<0.05). ConclusionAging rats exhibit obvious impairments in digestion and absorption functions, accompanied by a state of hepatic deficiency. The traditional Chinese medicine approach of tonifying liver Qi effectively ameliorates aging-related changes by modulating the R-spondin1/Wnt3a signaling pathway to mitigate intestinal senescence and enhance digestion and absorption functions, ultimately contributing to the delay of aging.
3.Mechanism of Qianyang Yuyin Granules Regulating NR3C2/ROS/ERK Pathway to Alleviate Aldosterone-induced Podocyte Injury
Yin LI ; Fang YUAN ; Junyao XU ; Cheng NING ; Yixuan WANG ; Lichao QIAN ; Haitao LI ; Jie LI
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(13):95-105
ObjectiveTo investigate the protective mechanism of Qianyang Yuyin granules (QYYY) on aldosterone-induced podocyte injury. MethodA total of 30 C57BL/6J mice were randomly divided into five groups: control group, model group, QYYY low dose (QYYY-L) group, QYYY high dose (QYYY-H) group, and spironolactone (SPL) group, with six mice in each group. Except for the control group, mice were implanted with osmotic minipumps and injected continuously with aldosterone (300 μg·kg-1·d-1) to induce renal injury. The drug administration group was given low and high doses (2.6, 5.2 g·kg-1·d-1) of QYYY and SPL (18 mg·kg-1·d-1) for 28 days. The renal pathological changes of mice were observed by hematoxylin-eosin (HE) staining and Masson staining. The expression levels of Nephrin, Desmin, B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X (Bax), cleaved Caspase-3, nuclear receptor subfamily 3 group C member 2 (NR3C2), extracellular regulated protein kinases (ERK), and phospho-ERK (p-ERK) in kidney tissue were detected by Western blot. The apoptosis levels of kidney tissue were detected by TdT-mediated dUTP nick and labeling (TUNEL) staining, and the superoxide dismutase (SOD) levels were detected. In vitro, the mice were divided into five groups: Control group, model group (aldosterone concentration of 200 nmol·L-1), QYYY-L group, QYYY medium dose (QYYY-M) group, and QYYY-H group (25, 50, and 100 mg·L-1). The effect of different concentrations of QYYY on the relative viability of aldosterone-induced podocytes was detected by cell proliferation and viability assay (CCK-8). The expressions of Nephrin, Desmin, Bax, Bcl-2, cleaved Caspase-3, NR3C2, and p-ERK/ERK were detected by Western blot. AnnexinV-FITC/PI flow cytometry was used to detect the apoptosis levels of podocytes. Reactive oxygen species (ROS) in podocytes were observed by DCFH-DA. ResultCompared with the control group, the model group showed structural pathological changes and fibrotic conditions in the kidney, increased apoptosis levels (P<0.01), and decreased SOD levels (P<0.01). Aldosterone concentration at 200 nmol·L-1 showed a significant decrease in podocyte activity (P<0.05). Podocytes in the model group showed structural pathological changes, disordered arrangement of intercellular microfilaments, increased apoptosis levels (P<0.01), and increased intracellular ROS levels (P<0.01). The protein expressions of Nephrin, Bcl-2, and p-ERK/ERK in kidney tissue and podocytes were decreased (P<0.05, P<0.01). The protein expressions of Desmin, Bax, cleaved Caspase-3, and NR3C2 were increased (P<0.05, P<0.01). Compared with the model group, QYYY alleviated the structural damage and fibrosis of the kidney, decreased the apoptosis levels (P<0.05, P<0.01), and enhanced the SOD content of the kidney (P<0.05, P<0.01). QYYY improved the activity of podocytes (P<0.05, P<0.01), restored the foot process structure of podocytes, and decreased apoptosis levels (P<0.01) and ROS levels of podocytes (P<0.01). The protein expressions of Nephrin, Bcl-2, and p-ERK/ERK in kidney tissue and podocytes were increased (P<0.05, P<0.01), and the protein expressions of Desmin, Bax, cleaved Caspase-3, and NR3C2 were down-regulated (P<0.05, P<0.01). ConclusionQYYY improves aldosterone-induced podocyte injury by regulating the NR3C2/ROS/ERK pathway.
4.Research Progress of Nrf2 and Ferroptosis in Tumor Drug Resistance.
Shuning HU ; Xinru ZOU ; Yixuan FANG ; Chengrui LIU ; Rui CHEN ; Lili JI
Chinese Journal of Lung Cancer 2023;26(10):765-773
Lung cancer is one of the most common cancers in the world, and its treatment strategy is mainly surgery combined with radiotherapy and chemotherapy. However, long-term chemotherapy will result in drug resistance, which is also one of the difficulties in the treatment of lung cancer. Ferroptosis is an iron-dependent and lipid peroxidation-driven non-apoptotic cell death cascade, occurring when there is an imbalance of redox homeostasis in the cell. Nuclear factor erythroid 2-related factor 2 (Nrf2) is key for cellular antioxidant responses. Numerous studies suggest that Nrf2 assumes an extremely important role in regulation of ferroptosis, for its various functions in iron, lipid, and amino acid metabolism, and so on. In this review, a brief overview of the research progress of ferroptosis over the past decade will be presented. In particular, the mechanism of ferroptosis and the regulation of ferroptosis by Nrf2 will be discussed, as well as the role of the Nrf2 pathway and ferroptosis in tumor drug resistance, which will provide new research directions for the treatment of drug-resistant lung cancer patients.
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Humans
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Ferroptosis
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NF-E2-Related Factor 2/genetics*
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Lung Neoplasms/genetics*
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Drug Resistance, Neoplasm
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Iron
5.Study on Prescription Optimization of Jiawei Foshou San Based on Mixed Uniform Design to Improve Cerebral Ischemia Effect
Xiaoyu WANG ; Yixuan ZHANG ; Min FANG ; Yijie WANG ; Qianqian MA ; Ling JIN ; Guotai WU
World Science and Technology-Modernization of Traditional Chinese Medicine 2023;25(9):3087-3097
Objective Screening of modified Foshou San to improve cerebral ischemia,determine the best prescription composition and the proper dose.Methods Using data mining method,the traditional Chinese medicine for hypertensive intracerebral hemorrhage(HICH)were screened,and cluster analysis was carried out to obtain Jiawei Foshou San combinations;According to the mixed uniform design U14(42×33×22),the auricular artery dilatation experiment and acute cerebral ischemia induced by saturated magnesium chloride in mice were used to observe the auricular artery dilatation index and survival time of mice,and the pharmacological effects of each prescription to improve cerebral ischemia were evaluated.On the basis of visual analysis of pharmacodynamics,stepwise multiple regression analysis was carried out,and the regression equation was used to calculate the best prescription composition and dose of Jiawei Foshou San.The optimized prescription was verified by acute cerebral ischemia experiment in mice.Results A total of 51 prescriptions that may be used for the treatment of HICH were selected by data mining,including 103 Chinese herbs,with a total frequency of 535 times.The results of mixed uniform design U14(42×33×22)test showed that the auricular artery index of mice in each prescription group of Jiawei Foshou San increased to varying degrees.The differences between prescription 4,8,12 and 13 were significant(P<0.05),and the differences between prescription 3,7,9,11 and 14 were extremely significant(P<0.01).The survival time of acute cerebral ischemia in mice was prolonged to varying degrees in each group of Jiawei Foshou San,and the difference between prescription 2-14 groups and the blank group was statistically significant(P<0.01).The prescription of the new Jiawei Foshou San was determined as 60 g of Astragalus membranaceus,60 g of Angelica sinensis,24 g of Ligusticum chuanxiong,15 g of Paeonia lactiflora and 9 g of Dilong from the intuitive analysis.The validation results showed that the high and middle dosage of the new Jiawei Foshou San could significantly prolong the breathing time,increase the number of breaths,and prolong the time of normal pressure hypoxia tolerance in mice with acute cerebral ischemia(P<0.01,P<0.05).Conclusion Using mixed uniform design combined with improving cerebral ischemia effect index can determine the best prescription composition and the best dose of Jiawei Foshou San,and the effect of improving cerebral ischemia is certain.
6.Analysis of influencing factors of clinical outcome after surgery and 131I treatment in patients with moderate-risk papillary thyroid cancer
Yixuan LI ; Chengxi ZHENG ; Maohua RAO ; Jiahui HUANG ; Danzhou FANG ; Yalan XIONG ; Gengbiao YUAN
Chinese Journal of Nuclear Medicine and Molecular Imaging 2023;43(9):538-542
Objective:To investigate the clinical outcome after surgery and first 131I treatment in patients with moderate-risk papillary thyroid cancer (PTC), and analyze the relevant factors that affect the therapeutic effect. Methods:From January 2018 to April 2019, 135 patients (48 males, 87 females; age (42.7±11.1) years) with moderate-risk PTC in the Second Affiliated Hospital of Chongqing Medical University were retrospectively analyzed. According to the 2015 American Thyroid Association (ATA) guidelines, patients were divided into excellent response (ER) group, inderteriminate response (IDR) group, biochemical incomplete response (BIR) group and structural incomplete response (SIR) group, of which IDR, BIR, SIR were collectively referred to as the non-ER group. χ2 test and Mann-Whitney U test were used to compare the general clinical features between the ER and non-ER groups, and then multivariate logistic regression analysis was performed. The predicted value of pre-ablation stimulated thyroglobulin (ps-Tg) to ER was assessed by ROC curve analysis. Results:The treatment responses of 94 patients were ER, and those of 41 were non-ER. The differences in tumor size (0.80(0.50, 1.10) vs 1.00(0.55, 1.50) cm; U=1 491.50, P=0.036), the number of metastatic lymph nodes (3(2, 5) vs 4(2, 12); U=1 422.00, P=0.015), metastatic lymph node size (0.50(0.30, 0.65) vs 0.50(0.30, 1.45) cm; U=1 396.50, P=0.013), metastatic lymph node involvement rate (50%(30%, 70%) vs 60%(50%, 85%); U=1 441.50, P=0.024), metastatic lymph node location (central/lateral: 76/18 vs 24/17; χ2=7.40, P=0.007) and ps-Tg level (2.1(0.8, 5.3) vs 14.0(3.2, 35.2) μg/L; U=680.00, P<0.001) were statistically significant between the ER and non-ER groups. Multivariate logistic regression analysis showed that ps-Tg (odds ratio ( OR)=1.200, 95% CI: 1.107-1.302, P<0.001) was an independent factor influencing ER. The cut-off value of ps-Tg for predicting ER was 7.38 μg/L, with the sensitivity and specificity of 68.3%(28/41) and 87.2%(82/94) respectively. Conclusion:Moderate-risk PTC patients with smaller tumor size, fewer metastatic lymph nodes, lower metastatic lymph node involvement rate, metastatic lymph nodes in central area, smaller metastatic lymph node size, and ps-Tg<7.38 μg/L have better therapeutic effect after initial 131I treatment.
7.Clinical Efficacy and Mechanism of Erzhi Tiangui Prescription in Treatment of Patients with Repeated Implantation Failure of Kidney Deficiency Syndrome Based on sPD-1 and Th17/Treg Cytokines
Yixuan WANG ; Conghui PANG ; Haicui WU ; Xiaona YU ; Xin XIN ; Fang LIAN
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(7):139-145
ObjectiveTo investigate the clinical efficacy and possible mechanism of Erzhi Tiangui prescription on repeated implantation failure (RIF) of kidney deficiency syndrome. MethodSeventy patients with RIF of kidney deficiency syndrome who underwent natural cycle frozen-thawed embryo transfer (FET) in the Reproductive and Genetic Center of the Affiliated Hospital of Shandong University of Traditional Chinese Medicine were enrolled and randomly divided into a treatment group (35 cases) and a control group (35 cases). Patients in the treatment group took oral Erzhi Tiangui prescription from the third day of each menstrual cycle two months before the FET cycle and continued to take it until the day of transplantation from the third day of the menstrual cycle in the month of transplantation. Those in the control group did not accept traditional Chinese medicine (TCM). In addition,10 patients who successfully achieved clinical pregnancy after the first natural cycle FET were screened from the reproductive medical record bank of this hospital and assigned to the normal group. Peripheral blood samples of patients in the three groups on the day of embryo transfer were collected from the specimen bank of the Reproductive and Genetic Center. Serum soluble programmed death molecule-1 (sPD-1),soluble programmed death molecule-ligand 1 (sPD-L1),transforming growth factor-β (TGF-β),interleukin-17 (IL-17), and interleukin-10 (IL-10) levels were measured by enzyme-linked immunosorbent assay (ELISA). The changes in kidney deficiency syndrome scores, the final biochemical pregnancy rates, clinical pregnancy rates, and embryo implantation rates of the treatment group and the control group before and after treatment were observed. ResultCompared with the normal group,the model group showed increased serum levels of sPD-1 and IL-17(r=0.347,P<0.05),decreased levels of IL-10 and TGF-β (P<0.01),and non-significant change in sPD-L1 level. Serum sPD-1 was positively correlated with IL-17 (P<0.05) and negatively correlated with IL-10(r=-0.521,P<0.01) and TGF-β(r=-0.457,P<0.01) in RIF patients with kidney deficiency syndrome. After TCM treatment,compared with the control group, the treatment group showed improved TCM syndrome score (P<0.05) and increased clinical pregnancy rate and embryo transfer rate(P<0.05),but there was no statistically significant difference in the biochemical pregnancy rate between the two groups. ConclusionAbnormal expression of sPD-1 in patients with RIF of kidney deficiency syndrome breaks the balance of T helper 17 (Th17)/regulatory T cell (Treg),which is not conducive to embryo implantation and pregnancy maintenance. Erzhi Tiangui prescription,a TCM for tonifying the kidney,can significantly improve the symptoms of kidney deficiency in patients with RIF of kidney deficiency syndrome,reduce the concentrations of sPD-1 and IL-17 in the peripheral serum,increase the levels of TGF-β and IL-10,regulate the peripheral Th17/Treg immune balance,and increase the implantation rate and clinical pregnancy rate,which has a high clinical value.
8.Research advances of natural biomaterials in promoting wound repair
Yixuan GAO ; Lingfeng WANG ; Te BA ; Xiaofang ZOU ; Shengjun CAO ; Junliang LI ; Fang LI ; Biao ZHOU
Chinese Journal of Burns 2023;39(5):481-486
Acute and chronic wounds seriously threaten patients' life health and quality of life, therefore, wound repair has become a hot topic of research for scholars at home and abroad in recent years. With the development of material science and tissue engineering, more and more biomaterials prepared from natural ingredients were used in basic research and clinical treatment of wound repair. Such biomaterials can be used as templates for wound tissue regeneration to induce autologous cell adhesion and migration, and promote the deposition of extracellular matrix, which have broad clinical application prospects. This paper reviews the characteristics and application advance of natural biomaterials which are popular in the field of wound repair, aiming to provide ideas for the research and development of new wound dressing and tissue engineering skin.
9.Progress of NRF2 Signaling Pathway in Promoting Proliferation of Non-small Cell Lung Cancer.
Yixuan FANG ; Xinru ZOU ; Shuning HU ; Lili JI
Chinese Journal of Lung Cancer 2022;25(10):735-741
The morbidity and mortality of lung cancer ranks among the top cancers in the world. Non-small cell lung cancer (NSCLC) is the main pathological type of lung cancer, with limited treatment options and poor prognosis. The nuclear factor E2-related factor 2 (NRF2) signaling pathway is highly mutated and activated in NSCLC, and promotes the malignant progression of lung cancer through various mechanisms. NRF2-targeted therapy will provide new treatment strategies for patients with NSCLC. This article will review the basic structure and response pathways of the NRF2 pathway, the mechanism of NRF2 regulating lung cancer cell proliferation, and the research and development progress of NRF2 inhibitors.
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Humans
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Carcinoma, Non-Small-Cell Lung/pathology*
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NF-E2-Related Factor 2/metabolism*
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Lung Neoplasms/pathology*
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Gene Expression Regulation, Neoplastic
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Signal Transduction
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Cell Proliferation
10.Effects of silicon dioxide exposure on lipid deposition and PI3K/AKT/mTOR signaling pathway in MLE-12 cells
Xiaohui HAO ; Jing SHAO ; Hui WU ; Yixuan JIN ; Lingli GUO ; Heliang LIU ; Fang YANG
Journal of Environmental and Occupational Medicine 2022;39(5):506-511
Background Lipid metabolism imbalance is tightly linked to the development and progression of multiple diseases. The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway is important for the regulation of lipid metabolism. However, whether silicosis is associated with lipid metabolic abnormalities has yet to be explored. Objective To observe the changes of lipid deposition, cholesterol, and phosphorylated proteins of PI3K/AKT/mTOR pathway in silicon dioxide (SiO2)-induced MLE-12 cells and to explore potential mechanism of lipid composition regulated though the pathway. Methods (1) MLE-12 cells were stimulated with 50 mg·L−1 SiO2 suspension, and divided into fourgroups: a control group and three SiO2 groups (12, 24, and 48 h of stimulation). (2) Cellproliferation was detected to determine an optimal dose of LY294002, an inhibitor of PI3K protein. LY294002 at 5 μmol·L−1 was used for further study, in which MLE-12 cells cultured for 48 h were divided into four groups: a control group; a 50 mg·L−1 SiO2 suspension stimulation group; a 50 mg·L−1 SiO2 suspension and 5 μmol·L−1 LY294002 treatment group; a 5 μmol·L−1 LY294002 treatment group. Total cholesterol (TC), free cholesterol (FC), cholesterol ester (CE; total cholesterol minus free cholesterol), and triglycerides (TG) were measured with enzyme assay kits. Lipid deposition was observed using Oil Red O staining. The expressions of p-PI3K, p-AKT, and p-mTOR proteins were detected by Western blotting. Results (1) The contents of TC, FC, and CE in the 50 mg·L−1 SiO2-induced MLE-12 cells were increased compared to those of the control group in a time-dependent manner by trend analysis, and the increment at 24 and 48 h were significant. By 48 h, the contents of cholesterol indicators were all elevated: TC from (2.242±0.181) mg·g−1 to (5.148±0.544) mg·g−1, FC from (1.923±0.158) mg·g−1 to (4.168±0.433) mg·g−1, and CE from (0.318±0.067) mg·g−1 to (0.978±0.134) mg·g−1, compared with the control group (P<0.01). The changes of TG were not significant (P>0.05). The SiO2 suspension induced orange-red particle deposition in the MLE-12 cells, especially at 48 h (P<0.01). The protein expression levels of p-PI3K, p-AKT, and p-mTOR in SiO2-stimulated MLE-12 cells were higher than those of the control groups with the prolongation of stimulation time, which peaked at 48 h (P<0.01). (2) The contents of TC, FC, and CE in MLE-12 cells of the SiO2 + LY294002 group were decreased, comparing to those of the SiO2 stimulation only group (P<0.01), companied with less orange-red lipid deposition, and suppressed protein expression levels of p-PI3K, p-AKT, and p-mTOR (P<0.01). Conclusion SiO2 could induce increases of cholesterol and lipid deposition through activation of PI3K/AKT/mTOR signaling pathway in MLE-12 cells.

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