scholarly journals L-Leucine Promotes STAT1 and ISGs Expression in TGEV-Infected IPEC-J2 Cells via mTOR Activation

2021 ◽  
Vol 12 ◽  
Author(s):  
Jian Du ◽  
Daiwen Chen ◽  
Bing Yu ◽  
Jun He ◽  
Jie Yu ◽  
...  
Keyword(s):  
Amino Acids ◽  
Western Blot ◽  
Mtor Inhibitor ◽  
Underlying Mechanism ◽  
Mtor Signaling ◽  
Transmissible Gastroenteritis Virus ◽  
Mtor Signaling Pathway ◽  
Infected Cells ◽  
P70 S6k ◽  
Transmissible Gastroenteritis

L-leucine (Leu), as one of the effective amino acids to activate the mTOR signaling pathway, can alleviate transmissible gastroenteritis virus (TGEV) infection. However, the underlying mechanism by which Leu alleviates the virus infection has not been fully characterized. In particular, how Leu impacts TGEV replication through mTOR signaling has yet to be elucidated. In the present study, we found that TGEV proliferated efficiently in intestinal porcine epithelial cells (IPEC-J2 cells) as evidenced by the increase in viral contents by flow cytometry, the inhibition of cell proliferation by CCK-8 assay as well as the reduction of PCNA level by western blot. Besides, western blot analysis showed that STAT1 expression was markedly reduced in TGEV-infected cells. The results of ELISA revealed the inhibition of ISGs (ISG56, MxA, and PKR) expressions by TGEV infection. TGEV-induced mTOR and its downstream p70 S6K and 4E-BP1, STAT1 and ISGs downregulation were blocked by an mTOR activator-MHY1485 but not by an mTOR inhibitor-RAPA. Concurrently, mTOR activation by MHY1485 reduced the contents of TGEV and vice versa. Furthermore, Leu reversed the inhibition of STAT1 and ISGs by activating mTOR and its downstream p70 S6K and 4E-BP1 in TEGV-infected cells. Our findings demonstrated that Leu promoted the expressions of STAT1 and ISGs via activating mTOR signaling in IPEC-J2 cells, aiming to prevent TGEV infection.

scholarly journals Total saponins of Bolbostemma paniculatum (maxim.) Franquet exert antitumor activity against MDA-MB-231 human breast cancer cells via inhibiting PI3K/Akt/mTOR pathway

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Jian-Wei Dou ◽  
Rong-Guo Shang ◽  
Xiao-Qin Lei ◽  
Kang-Le Li ◽  
Zhan-Zi Guo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Signaling Pathway ◽  
Mtor Inhibitor ◽  
Therapeutic Potential ◽  
Underlying Mechanism ◽  
Mtor Pathway ◽  
Mtor Signaling ◽  
Pi3k Inhibitor ◽  
Mtor Signaling Pathway ◽  
And Migration

Abstract Background The aim of the present study was to examine the effects of the Bolbostemma paniculatum (Maxim.) Franquet (BP) active compound, BP total saponins (BPTS), on MDA-MB-231 cells, and investigate the underlying mechanism regarding BPTS-mediated attenuation of the PI3K/Akt/mTOR pathway. Methods The effect of BPTS on cytotoxicity, induction of apoptosis and migration on MDA-MB-231 cells at three different concentrations was investigated. A CCK-8 assay, wound-healing assay and flow cytometry were used to demonstrate the effects of BPTS. Additionally, expression of the primary members of the PI3K/Akt/mTOR signaling pathway was assessed using western blotting. To verify the underlying mechanisms, a PI3K inhibitor and an mTOR inhibitor were used. Results BPTS inhibited proliferation of MDA-MB-231 cells with an IC50 value of 10 μg/mL at 48 h. BPTS inhibited migration of MDA-MB-231 cells, and the western blot results demonstrated that BPTS reduced p-PI3K, p-Akt and p-mTOR protein expression levels in MDA-MB-231 cells. Additionally, the results were confirmed using a PI3K inhibitor and an mTOR inhibitor. BPTS decreased proliferation and migration of MDA-MB-231 cells possibly through inhibiting the PI3K/Akt/mTOR signaling pathway. Conclusions The results highlight the therapeutic potential of BPTS for treating patients with triple-negative breast cancer.

scholarly journals A suppressive oligodeoxynucleotide expressing TTAGGG motifs modulates cellular energetics through the mTOR signaling pathway

2019 ◽  
Vol 32 (1) ◽  
pp. 39-48 ◽  
Author(s):  
Volkan Yazar ◽  
Gizem Kilic ◽  
Ozlem Bulut ◽  
Tugce Canavar Yildirim ◽  
Fuat C Yagci ◽  
...  
Keyword(s):  
Mtor Inhibitor ◽  
Mammalian Target Of Rapamycin ◽  
Underlying Mechanism ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Tissue Destruction ◽  
Murine Splenocytes ◽  
Immune Mediated ◽  
Mtor Phosphorylation ◽  
Cellular Energetics

Abstract Abstract Immune-mediated inflammation must be down-regulated to facilitate tissue remodeling during homeostatic restoration of an inflammatory response. Uncontrolled or over-exuberant immune activation can cause autoimmune diseases, as well as tissue destruction. A151, the archetypal example of a chemically synthesized suppressive oligodeoxynucleotide (ODN) based on repetitive telomere-derived TTAGGG sequences, was shown to successfully down-regulate a variety of immune responses. However, the degree, duration and breadth of A151-induced transcriptome alterations remain elusive. Here, we performed a comprehensive microarray analysis in combination with Ingenuity Pathway Analysis (IPA) using murine splenocytes to investigate the underlying mechanism of A151-dependent immune suppression. Our results revealed that A151 significantly down-regulates critical mammalian target of rapamycin (mTOR) activators (Pi3kcd, Pdpk1 and Rheb), elements downstream of mTOR signaling (Rps6ka1, Myc, Stat3 and Slc2a1), an important component of the mTORC2 protein complex (Rictor) and Mtor itself. The effects of A151 on mTOR signaling were dose- and time-dependent. Moreover, flow cytometry and immunoblotting analyses demonstrated that A151 is able to reverse mTOR phosphorylation comparably to the well-known mTOR inhibitor rapamycin. Furthermore, Seahorse metabolic assays showed an A151 ODN-induced decrease in both oxygen consumption and glycolysis implying that a metabolically inert state in macrophages could be triggered by A151 treatment. Overall, our findings suggested novel insights into the mechanism by which the immune system is metabolically modulated by A151 ODN.

scholarly journals M2 macrophage-derived exosomal microRNAs inhibit cell migration and invasion in gliomas through PI3K/AKT/mTOR signaling pathway

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Jie Yao ◽  
Zefen Wang ◽  
Yong Cheng ◽  
Chao Ma ◽  
Yahua Zhong ◽  
...  
Keyword(s):  
Cell Migration ◽  
Western Blot ◽  
Signaling Pathway ◽  
Target Gene ◽  
Glioma Cells ◽  
Mtor Signaling ◽  
Migration And Invasion ◽  
M2 Macrophage ◽  
Mtor Signaling Pathway ◽  
Cell Migration And Invasion

Abstract Background Glioma, the most common primary brain tumor, account Preparing figures for 30 to 40% of all intracranial tumors. Herein, we aimed to study the effects of M2 macrophage-derived exosomal microRNAs (miRNAs) on glioma cells. Methods First, we identified seven differentially expressed miRNAs in infiltrating macrophages and detected the expression of these seven miRNAs in M2 macrophages. We then selected hsa-miR-15a-5p (miR-15a) and hsa-miR-92a-3p (miR-92a) for follow-up studies, and confirmed that miR-15a and miR-92a were under-expressed in M2 macrophage exosomes. Subsequently, we demonstrated that M2 macrophage-derived exosomes promoted migration and invasion of glioma cells, while exosomal miR-15a and miR-92a had the opposite effects on glioma cells. Next, we performed the target gene prediction in four databases and conducted target gene validation by qRT-PCR, western blot and dual luciferase reporter gene assays. Results The results revealed that miR-15a and miR-92a were bound to CCND1 and RAP1B, respectively. Western blot assays demonstrated that interference with the expression of CCND1 or RAP1B reduced the phosphorylation level of AKT and mTOR, indicating that both CCND1 and RAP1B can activate the PI3K/AKT/mTOR signaling pathway. Conclusion Collectively, these findings indicate that M2 macrophage-derived exosomal miR-15a and miR-92a inhibit cell migration and invasion of glioma cells through PI3K/AKT/mTOR signaling pathway.

scholarly journals Regulation of osteoblast autophagy based on PI3K/AKT/mTOR signaling pathway study on the effect of β-ecdysterone on fracture healing

2021 ◽  
Author(s):  
Yanghua Tang ◽  
Yafeng Mo ◽  
Dawei Xin ◽  
Zhenfei Xiong ◽  
Linru Zeng ◽  
...  
Keyword(s):  
Western Blot ◽  
Fracture Healing ◽  
Underlying Mechanism ◽  
Immunofluorescence Assay ◽  
The State ◽  
Expression Level ◽  
Pathological State ◽  
Mtor Signaling Pathway ◽  
X Ray ◽  
Alp Activity

Purpose: To investigate the effects of β-ecdysterone on fracture healing and the underlying mechanism. Methods: MTT assay was used to detect the cell viability and alkaline phosphatase (ALP) activity was measured using a commercial kit. AO/PI and flow cytometry assays were used to determine the state of apoptosis of osteoblasts. The expression level of RunX2, ATG7 and LC3 was evaluated by qRT-PCR and Western blot assays. X-ray and HE staining were conducted on the fractured femur to evaluate the pathological state. Immunohistochemical assay was used to detect the expression level of Beclin-1 and immunofluorescence assay was used to measure the expression level of LC3 in the fractured femurs. Western blot was utilized to determine the expression level of PI3K, p-AKT1, AKT1, p-mTOR, mTOR, p-p70S6K, and p70S6K. Results: The ALP activity and expression of RunX2 in fractured osteoblasts were significantly suppressed by 3-methyladenine and elevated by rapamycin, 60, and 80 μM β-ecdysterone. The apoptotic state of fractured osteoblasts was enhanced by 3-methyladenine and alleviated by rapamycin, 60, and 80 μM β-ecdysterone. The state of autophagy both in fractured osteoblasts and femurs was inhibited by 3-methyladenine and facilitated by rapamycin and β-ecdysterone. Compared to control, Garrett score in 3-methyladenine group was significantly decreased and promoted in rapamycin and β-ecdysterone groups, accompanied by ameliorated pathological state. Lastly, the PI3K/AKT/mTOR pathway both in fractured osteoblasts and femurs was activated by 3-methyladenine and inhibited by rapamycin and β-ecdysterone. Conclusion: β-ecdysterone might facilitate fracture healing by activating autophagy through suppressing PI3K/AKT/mTOR signal pathway.

SIK2 Promotes Cisplatin Resistance Induced by Aerobic Glycolysis in Breast Cancer Cells through PI3K/AKT/mTOR Signaling Pathway

2020 ◽  
Author(s):  
Shoukai Zong ◽  
Wei Dai ◽  
Wencheng Fang ◽  
Xiangting Guo ◽  
Kai Wang
Keyword(s):  
Breast Cancer ◽  
Western Blot ◽  
Cancer Cells ◽  
Signaling Pathway ◽  
Breast Cancer Cells ◽  
Cisplatin Resistance ◽  
Aerobic Glycolysis ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Protein Levels

Abstract Objective This study aimed to investigate the effect of SIK2 on cisplatin resistance induced by aerobic glycolysis in breast cancer cells and its potential mechanism. Methods qRT-PCR and Western blot were used to detect SIK2 mRNA and protein levels. Cisplatin (DDP) resistant cell lines of breast cancer cells were established, CCK-8 was used to measure and evaluate the viability, and Transwell was used to evaluate the cell invasion capability. Flow cytometry was adopted to evaluate the apoptosis rate. The glycolysis level was evaluated by measuring glucose consumption and lactic acid production. The protein levels of p-PI3K, p- protein kinase B (Akt) and p-mTOR were determined by western blot. Results SIK2 is highly expressed in breast cancer tissues and cells compared with adjacent tissues and normal human breast epithelial cells, and has higher diagnostic value for breast cancer. Silencing SIK2 expression can inhibit proliferation and invasion of breast cancer cells and induce their apoptosis. In addition, SIK2 knockdown inhibits glycolysis, reverses the resistance of drug-resistant cells to cisplatin, and inhibits PI3K/AKT/mTOR signaling pathway. When LY294002 is used to inhibit PI3K/AKT/mTOR signaling pathway, the effect of Sh-SIK2 on aerobic glycolysis of breast cancer cells can be reversed. Conclusion SIK2 can promote cisplatin resistance caused by aerobic glycolysis of breast cancer cells through PI3K/AKT/mTOR signaling pathway, which may be a new target to improve cisplatin resistance of breast cancer cells.

scholarly journals Ginsenoside Rg3 Suppresses Proliferation and Induces Apoptosis in Human Osteosarcoma

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Yi Li ◽  
Jinying Lu ◽  
Furong Bai ◽  
Yanan Xiao ◽  
Yiran Guo ◽  
...  
Keyword(s):  
Western Blot ◽  
Signaling Pathway ◽  
Mtor Signaling ◽  
Assay Method ◽  
Osteosarcoma Cell ◽  
Dependent Manner ◽  
Ginsenoside Rg3 ◽  
Mtor Signaling Pathway ◽  
Human Osteosarcoma ◽  
Human Osteosarcoma Cells

Osteosarcoma is the most common primary malignancy of bone in children and the elderly. Recently, more and more researches have demonstrated that Ginsenoside Rg3 (Rg3) is involved in chemotherapy resistance in many cancer, making it a promising Chinese herbal monomer for oncotherapy. In this study, we investigated the efficacy of Rg3 in human osteosarcoma cell lines (MG-63, U-2OS, and SaOS-2). Cell proliferation was measured by CCK8 assay. The migration of cells was examined using the scratch assay method. Quantification of apoptosis was assessed further by flow cytometry. In addition, the expression of apoptosis-related genes (caspase9, caspase3, Bcl2, and Bax) were investigated using RT-PCR. We further investigated the protein level expression of Bcl 2, cleaved-caspase3, and PI3K/AKT/mTOR signaling pathway factors by Western blot assay. Our results revealed that Rg3 inhibited the proliferation and migration of human osteosarcoma cells and induced apoptosis in a concentration- and time-dependent manner. Western blot results showed that Rg3 reduced the protein expression of Bcl2 and PI3K/AKT/mTORbut increased the levels of cleaved-caspase3. Therefore, we hypothesized Rg3 inhibits the proliferation of osteosarcoma cell line and induces their apoptosis by affecting apoptosis-related genes (Bcl2, caspase3) as well as the PI3K/AKT/mTOR signaling pathway. To conclude, Rg3 is a new therapeutic agent against osteosarcoma.

scholarly journals EPHA2 Promotes the Invasion and Migration of Human Tongue Squamous Cell Carcinoma Cal-27 Cells by Enhancing AKT/mTOR Signaling Pathway

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Fengqin Wang ◽  
Hanzhong Zhang ◽  
Zhigang Cheng
Keyword(s):  
Cell Cycle ◽  
Signaling Pathway ◽  
Mtor Inhibitor ◽  
Mtor Signaling ◽  
Biological Behavior ◽  
Migration And Invasion ◽  
Mtor Signaling Pathway ◽  
Akt Inhibitor ◽  
Invasion And Migration ◽  
And Migration

EPHA2 is a member of the ephrin receptor tyrosine kinase family and is closely related to the malignant tumor progression. The effect of EPHA2 on OSCC is not clear. This study explored the role of EPHA2 and AKT/mTOR signaling pathways in Cal-27 cell invasion and migration. The expression of EPHA2 and EPHA4 in human OSCC and normal oral tissue was detected by immunohistochemistry. EPHA2-overexpressing and EPHA2-knockdown Cal-27 cells were established, and the cells were treated with an AKT inhibitor (MK2206) and mTOR inhibitor (RAD001). The expression of EPHA2 was detected by qRT-PCR, cell proliferation was evaluated by MTT assay, cell migration and invasion were examined by scratch and Transwell assay, and cell morphology and apoptosis were assessed by Hoechst 33258 staining. Western blot was performed to detect the expression of proteins related to AKT/mTOR signaling, cell cycle, and pseudopod invasion. EPHA2 and EPHA4 were highly expressed in clinical human OSCC. Overexpression of EPHA2 promoted the proliferation, migration, and invasion of Cal-27 cells, inhibited cell cycle blockage and apoptosis, and enhanced the activity of the AKT/mTOR signaling pathway. MK2206 (AKT inhibitor) and RAD001 (mTOR inhibitor) reversed the effect of EPHA2 overexpression on the biological behavior of Cal-27 cells. EPHA2 promotes the invasion and migration of Cal-27 human OSCC cells by enhancing the AKT/mTOR signaling pathway.

MicroRNA-1271-5p inhibits the tumorigenesis of ovarian cancer through targeting E2F5 and negatively regulates the mTOR signaling pathway

2020 ◽  
Author(s):  
Qin Li ◽  
Junyu Shi ◽  
Xiaoli Xu
Keyword(s):  
Ovarian Cancer ◽  
Western Blot ◽  
Signaling Pathway ◽  
Blot Analysis ◽  
Mtor Signaling ◽  
Migration And Invasion ◽  
Mtor Signaling Pathway ◽  
Pcr Assay ◽  
Qrt Pcr ◽  
Worse Prognosis

Abstract Background: MicroRNA-1271-5p (miR-1271-5p) has been reported to participate in the progression of many malignancies. However, the molecular mechanism of miR-1271-5p still remains vague in ovarian cancer (OC). Therefore, we explored the effect of miR-1271-5p in the development of OC in present study.Methods: We measured the miR-1271-5p expression via qRT-PCR assay. Western blot analysis was employed to examine protein expression. Then, the functional mechanism of miR-1271-5p was analyzed by MTT, Transwell and dual luciferase assays.Results: Downregulation of miR-1271-5p was found in OC, which can predict worse prognosis in OC patients. Further, miR-1271-5p directly targets E2F5 in OC. And miR-1271-5p restrained the proliferation, migration and invasion of OC cells via targeting E2F5. Additionally, upregulation of E2F5 was observed in OC, which predicted unfavorable prognosis in OC patients. Besides that, miR-1271-5p suppressed EMT and mTOR pathway in OC.Conclusion: MiR-1271-5p inhibited the tumorigenesis of OC through targeting E2F5 and negatively regulated the mTOR signaling pathway.

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