scholarly journals Pterostilbene Alleviates Cholestasis by Promoting SIRT1 Activity in Hepatocytes and Macrophages

2021 ◽  
Vol 12 ◽  
Author(s):  
Chuanrui Ma ◽  
Jiaqing Xiang ◽  
Guixiao Huang ◽  
Yaxi Zhao ◽  
Xinyu Wang ◽  
...  

Background and purpose: FXR is a promising target for the treatment of human cholestatic liver disease (CLD). SIRT1 is a deacetylase which promotes FXR activity through deacetylating FXR. Pterostilbene (PTE) is an activator of SIRT1. However, the role of PTE in cholestasis has so far not been investigated. We examined whether PTE treatment alleviate liver injury in DDC or ANIT-induced experimental cholestasis, and explored the underlying mechanisms.Experimental approach: Mice with DDC- or ANIT-induced cholestasis were treated with different dose of PTE. Primary hepatocytes and bone marrow derived macrophages were used in vitro to assess the molecular mechanism by which PTE may improve CLD. Identical doses of UDCA or PTE were administered to DDC- or ANIT-induced cholestasis mice.Key results: PTE intervention attenuated DDC or ANIT-induced cholestasis. PTE inhibited macrophage infiltration and activation in mouse liver through the SIRT1-p53 signaling pathway, and it improved hepatic bile metabolism through the SIRT1-FXR signaling pathway. Compare with UDCA, the same doses of PTE was more effective in improving cholestatic liver injury caused by DDC or ANIT.Conclusion and implications: SIRT1 activation in macrophages may be an effective CLD treatment avenue. Using CLD models, we thus identified PTE as a novel clinical candidate compound for the treatment of CLD.

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 7002
Author(s):  
Longlin Zhang ◽  
Mengmeng Ma ◽  
Zhengyi Li ◽  
Haihan Zhang ◽  
Xi He ◽  
...  

L-theanine is a nonprotein amino acid found in tea leaves and has been widely used as a safe food additive in beverages or foods because of its varied bioactivities. The aim of this study was to reveal the in vitro gastrointestinal protective effects of L-theanine in DSS-induced intestinal porcine enterocyte (IPEC-J2) cell models using molecular and metabolic methods. Results showed that 2.5% dextran sulfate sodium (DSS) treatment inhibited the cell proliferation of IPEC-J2 and blocked the normal operation of the cell cycle, while L-theanine pretreatment significantly preserved these trends to exert protective effects. L-theanine pre-treatment also up-regulated the EGF, CDC2, FGF2, Rb genes and down-regulated p53, p21 proliferation-related mRNA expression in DSS-treated cells, in accompany with p53 signaling pathway inhibition. Meanwhile, metabolomics analysis revealed that L-theanine and DSS treated IPEC-J2 cells have different metabolomic profiles, with significant changes in the key metabolites involved in pyrimidine metabolism and amino acid metabolism, which play an important role in nucleotide metabolism. In summary, L-theanine has a beneficial protection in DSS-induced IPEC-J2 cells via promoting proliferation and regulating metabolism disorders.


2020 ◽  
Author(s):  
Fazhan Wang ◽  
Jun Zheng ◽  
Yongyong Yang ◽  
Jie Yang ◽  
Ting Luo ◽  
...  

Abstract Background Naa10p (N-α-Acetyltransferase 10 protein) was reported to be involved in tumor invasion and metastasis in several of tumors. However, the role and mechanism of Naa10p mediated invasion and metastasis in oral squamous cell carcinoma (OSCC) remains undetermined. Methods The functional role of Naa10p in OSCC cells were determined using Transwell assay in vitro and xenograft tumorigenesis in nude mice. Immunoprecipitation, GST-pull down assays and immunofluorescence were performed to confirm the interaction between Naa10p and RelA/p65 in OSCC cells. Lastly, luciferase reporter assays, chromatin immunoprecipitation (ChIP) and western blot were used to evalute the effect of Naa10p expression on the Pirh2-p53 signaling pathway. Results Naa10p inhibits cell migration and invasion in vitro and attenuates the xenograft tumorigenesis in nude mice. Mechanistically, there is a physical interaction between Naa10p and RelA/p65 in OSCC cells, thereby preventing RelA/p65-mediated transcriptional activation of Pirh2. Consequently, inhibition of Pirh2 increased p53 level and suppressed the expression of p53 downstream targets, MMP-2 and MMP-9. Conclusion Naa10p function as a tumor metastasis suppressor in the progression of OSCC by targeting Pirh2-p53 axis, and might be a prognostic marker as well as a therapeutic target for OSCC.


Author(s):  
Софья Дмитриевна Сенотрусова ◽  
Ольга Фалалеевна Воропаева ◽  
Юрий Иванович Шокин

Работа посвящена практическому использованию минимальных математических моделей динамики сигнального пути p53 для описания достаточно широкого круга лабораторных экспериментов, в которых взаимодействие p53 и белковингибиторов p53 опосредуется микроРНК, образующими с p53 петлю положительной обратной связи. Представлены базовая модель, разработанные на ее основе новые минимальные модели, алгоритм численного решения прямых и обратных коэффициентных задач и результаты сопоставления полученных численных решений с экспериментальными данными о динамике уровней белков p53, p21, Bax, белков-ингибиторов Mdm2, Wip1, Sirt1 и различных микроРНК (miR-16, miR-34a, miR-192, miR-194, miR-215) в условиях стрессовых воздействий. С привлечением полученных математических моделей исследованы базовые механизмы функционирования сигнального пути p53 в условиях, приближенных к условиям конкретных лабораторных экспериментов in vitro и in vivo. Продемонстрированы синергический эффект гиперактивации сигнального пути p53, в котором задействованы микроРНК, и механизмы бимодального переключения. Показана ключевая роль p53-зависимых микроРНК в реализации некоторых гипотетических терапевтических стратегий, связанных с управлением механизмом активации апоптоза клеток. В рамках принятой базовой модели даны оценки вероятности рассогласования в диагностике дегенеративных заболеваний, основанной на анализе уровня p53зависимых микроРНК и p53, при слабой и умеренной дерегуляции микроРНК. This study addresses the practical use of minimal mathematical models of the dynamics of a hypothetical system of the p53 signaling pathway to describe a fairly wide range of laboratory experiments. In such system, the interaction of p53 and p53 inhibitor proteins is mediated by microRNAs that form a positive feedback loop with p53. A basic model, new minimal models developed on its basis, an algorithm for the numerical solution of direct and inverse coefficient problems, and the results of comparing the obtained numerical solutions with experimental data on the dynamics of the levels of p53, p21, Bax proteins, inhibitor proteins Mdm2, Wip1, Sirt1, and various microRNAs (miR-16, miR-34a, miR-192, miR-194, miR-215) under stress conditions are presented. In numerical experiments, the main mechanisms of the p53 signaling pathway were investigated. A synergistic effect of hyperactivation of the p53 signaling pathway and bimodal switching mechanisms has been demonstrated. We show the key role of p53-dependent microRNAs in the implementation of some hypothetical therapeutic strategies associated with the control mechanism for activation of cells apoptosis. Within the framework of the accepted basic model, we estimated the probability of mismatch in the diagnosis of the patient’s status. The status is based on the analysis of the level of p53-dependent microRNAs and p53, with weak and moderate deregulation of microRNAs.


2020 ◽  
Author(s):  
Yuanji Xu ◽  
Kunshou Zhu ◽  
Junqiang Chen ◽  
Liyan Lin ◽  
Zhengrong Huang ◽  
...  

Abstract SASS6 encodes for the Homo sapiens SAS-6 centriolar assembly protein and is important for proper centrosome formation. Although centrosomes are amplified in a wide variety of tumor types, abnormally high SASS6 expression had previously only been identified in colon cancer. Moreover, the role of SASS6 in esophageal squamous cell carcinoma (ESCC) pathogenesis has not yet been elucidated. The aim of this study was to investigate the role and mechanisms of SASS6 in ESCC. In this study, we found that the mRNA and protein levels of SASS6 were increased in human ESCC samples. In addition, SASS6 protein expression was associated with the esophageal cancer stage and negatively affected survival of patients with ESCC. Furthermore, silencing of SASS6 inhibited cell growth and promoted apoptosis of ESCC cells in vitro and inhibited xenograft tumor formation in vivo. A genetic cluster and pathway analysis showed that SASS6 regulated the p53 signaling pathway. Western blot demonstrated that CCND2, GADD45A and EIF4EBP1 protein expression decreased and that TP53 protein expression increased after the knockdown of SASS6 in ESCC cells. Therefore, SASS6 promoted the proliferation of esophageal cancer by inhibiting the p53 signaling pathway. SASS6 has potential as a novel tumor marker and a therapeutic target for ESCC.


2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Yangmei Zhou ◽  
Li Yang ◽  
Xiaoxi Zhang ◽  
Rui Chen ◽  
Xiuqiong Chen ◽  
...  

Glioblastoma is a common malignant tumor in the central nervous system with an extremely poor outcome; understanding the mechanisms of glioblastoma at the molecular level is essential for clinical treatment. In the present study, we used bioinformatics analysis to identify potential biomarkers associated with prognosis in glioblastoma and elucidate the underlying mechanisms. The result revealed that 552 common genes were differentially expressed between glioblastoma and normal tissues based on TCGA, GSE4290, and GSE 50161 datasets. Gene Oncology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and protein-protein interaction (PPI) network were carried out to gain insight into the actions of differentially expressed genes (DEGs). As a result, 20 genes (CALB1, CDC20, CDCA8, CDK1, CEP55, DLGAP5, KIF20A, KIF4A, NDC80, PBK, RRM2, SYN1, SYP, SYT1, TPX2, TTK, VEGFA, BDNF, GNG3, and TOP2A) were found as hub genes via CytoHubba in Cytoscape and functioned mainly by participating in cell cycle and p53 signaling pathway; among them, RRM2 and CEP55 were considered to have relationship with the prognosis of glioblastoma, especially RRM2. High expression of RRM2 was consistent with shorter overall survival time. In conclusion, our study displayed the bioinformatic analysis methods in screening potential oncogenes in glioblastoma and underlying mechanisms. What is more is that we successfully identified RRM2 as a novel biomarker linked with prognosis, which might be expected to be a promising target for the therapy of glioblastoma.


Oncotarget ◽  
2017 ◽  
Vol 8 (25) ◽  
pp. 40982-40993 ◽  
Author(s):  
Haili Zhang ◽  
Xiao Tan ◽  
Daqian Yang ◽  
Jingjing Lu ◽  
Biying Liu ◽  
...  

2016 ◽  
Vol 12 (11) ◽  
pp. e1006026 ◽  
Author(s):  
Cory H. White ◽  
Bastiaan Moesker ◽  
Nadejda Beliakova-Bethell ◽  
Laura J. Martins ◽  
Celsa A. Spina ◽  
...  

Author(s):  
Xiaojia Min ◽  
Tingting Zhang ◽  
Ying Lin ◽  
Bo Wang ◽  
Kean Zhu

Ovarian cancer is the most lethal diseases among women. The chemo-resistance has been a big challenge for the cancer treatment. It has been reported that metformin may inhibit ovarian cancer and is able to impede the development of drug resistance, but the molecular mechanisms remain elusive. In this study, we explored the molecular roles of metformin in Parkin expression and p53 ubiquitination in chemo-resistant ovarian cancer cells. Firstly, ovarian cancer and chemo-resistant ovarian cancer cells were selected for determining the expression of Parkin, p53, and p53 signaling pathway-related factors. Then the cell proliferation and viability after loss- and gain-of-function assays were measured. Besides, immunoprecipitation (IP) was used to determine the interactions between Parkin and p53, and the ubiquitination level of p53 was measured using in vitro ubiquitination assay. Finally, the degradation of p53 proteasome regulated by Parkin was monitored using the MG132 proteasome inhibitor. We found that metformin significantly inhibited the growth of ovarian cancer parental cells and chemo-resistant cells, and metformin promoted Parkin expression in chemo-resistant cells. Further, up-regulated Parkin expression promoted the ubiquitination and degradation of p53, and metformin inhibited the expression of p53 to suppress the proliferation of chemo-resistant ovarian cancer cells. Mechanistically, metformin could inhibit the growth of ovarian cancer cells by promoting the Parkin-induced p53 ubiquitination. Altogether, our study demonstrated an inhibitory role of metformin in the growth of chemo-resistant cancer cells through promoting the Parkin-induced p53 ubiquitination, which provides a novel mechanism of metformin for treating ovarian cancer.


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