scholarly journals Time-Dependent Changes in Hepatic Sphingolipid Accumulation and PI3K/Akt/mTOR Signaling Pathway in a Rat Model of NAFLD

2021 ◽  
Vol 22 (22) ◽  
pp. 12478
Author(s):  
Klaudia Sztolsztener ◽  
Karolina Konstantynowicz-Nowicka ◽  
Ewa Harasim-Symbor ◽  
Adrian Chabowski
Keyword(s):  
Signaling Pathway ◽  
High Performance ◽  
Glucose Transporter ◽  
Significant Inhibition ◽  
Mtor Signaling ◽  
Time Dependent ◽  
Standard Diet ◽  
Mtor Signaling Pathway ◽  
Akt Phosphorylation ◽  
Male Wistar Rats

Increased lipid bioavailability in a diet favors lipid accumulation, enhancing hepatic lipotoxicity and contributing to insulin resistance (IR) development. The aim of our study was to examine time-dependent alterations in the intrahepatic content of sphingolipids and insulin signaling pathway in rats fed a high-fat diet (HFD). The experiment was conducted on male Wistar rats receiving a standard diet or HFD for five weeks. At the end of each experimental feeding week, liver sphingolipids were determined using high-performance liquid chromatography. The expression of proteins from the sphingolipid pathway and glucose transporter expression were assessed by Western blot. The content of phosphorylated form of proteins from the insulin pathway was detected by a multiplex assay kit. Our results revealed that HFD enhanced hepatic ceramide deposition by increasing the expression of selected proteins from sphingomyelin and salvage pathways in the last two weeks. Importantly, we observed a significant inhibition of Akt phosphorylation in the first week of HFD and stimulation of PTEN and mTOR phosphorylation at the end of HFD. These changes worsened the PI3K/Akt/mTOR signaling pathway. We may postulate that HFD-induced reduction in the insulin action in the time-dependent matter was exerted by excessive accumulation of sphingosine and sphinganine rather than ceramide.

scholarly journals Hyperin Alleviates Triptolide-Induced Ovarian Granulosa Cell Injury by Regulating AKT/TSC1/mTORC1 Signaling

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Fang You ◽  
Junyan Cao ◽  
Li Cheng ◽  
Xiaogu Liu ◽  
Li Zeng
Keyword(s):  
Signaling Pathway ◽  
Granulosa Cell ◽  
High Performance ◽  
Cell Injury ◽  
Ovarian Function ◽  
Interaction Network ◽  
Mtor Signaling ◽  
Network Pharmacology ◽  
Mtor Signaling Pathway ◽  
Mtorc1 Signaling

Premature ovarian insufficiency (POI) is characterized by the loss of ovarian function before 40 years of age and affects approximately 1% of women worldwide. Caragana sinica is a traditional Miao (a Chinese ethnic minority) medicine that improves ovarian function and follicular development. In the present study, we aimed to investigate the effect of active ingredients of C. sinica on POI and determine underlying mechanisms. Herein, the chemical composition of the C. sinica compound was analyzed using ultra-high-performance liquid chromatography, which identified hyperin (HR) as one of the main ingredients in C. sinica. Then, interaction targets of HR and POI were predicted and analyzed using network pharmacology and bioinformatics. The effect of HR on triptolide (TP)-induced granulosa cell injury was evaluated, and the underlying mechanism was explored based on bioinformatic results. A total of 100 interaction targets for POI and HR were obtained. The protein-protein interaction network of identified interaction targets emphasized the topological importance of AKT1. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that HR might regulate POI by modulating the mechanistic target of rapamycin (mTOR) signaling pathway. In addition, the KEGG graph of the mTOR signaling pathway revealed that AKT phosphorylation inhibits the TSC1/2, while TSC1/2 activation inhibits the expression of mTORC1. The fundamental experiment revealed that HR increased proliferation, progesterone receptor levels, and estradiol levels decreased by TP in KGN cells. Additionally, HR alleviated TP-induced apoptosis and G1/G1 phase arrest in KGN cells. Western blotting demonstrated that HR increased the phosphorylation of AKT and mTORC1 and decreased TSC1 expression in TP-induced KGN cells. Collectively, our findings revealed that HR alleviates TP-induced granulosa cell injury by regulating AKT/TSC1/mTORC1 signaling, providing insight into the treatment of POI.

scholarly journals Burn Ointment Promotes Cutaneous Wound Healing by Modulating the PI3K/AKT/mTOR Signaling Pathway

2021 ◽  
Vol 12 ◽  
Author(s):  
Dali Gan ◽  
Qiyuan Su ◽  
Hanwen Su ◽  
Li Wu ◽  
Jun Chen ◽  
...  
Keyword(s):  
Wound Healing ◽  
Signaling Pathway ◽  
High Performance ◽  
Scientific Evidence ◽  
Latency Period ◽  
Analgesic Efficacy ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Hot Plate ◽  
Anti Inflammatory

Burn ointment (BO) is a clinically useful medicine for the treatment of burns and scalds. However, there is no enough scientific evidence to report the effect of BO on wound healing and its analgesic and anti-inflammatory efficacy. The aim of this work was to evaluate the anti-inflammatory and analgesic efficacy of BO and to reveal the potential wound healing properties and related mechanisms of BO. In this work, the content of active ingredients of BO was determined by high-performance liquid chromatography (HPLC). Two animal models of inflammation were used to study its anti-inflammatory activity, and a hot plate method was used to evaluate its analgesic effect. In addition, mouse incision and rat burn models were used to investigate the effect of BO on the anti-inflammatory and wound healing mechanisms. The results showed that BO was safe for topical application, and BO could significantly inhibit auricular swelling in mice and paw swelling in rats and significantly prolong the latency period of paw licking in the hot plate experiment in mice. It can also accelerate wound healing and repair scars by promoting the formation of new epithelial tissues in rat burn models. In addition, BO significantly downregulated the serum level of TNF-α and significantly increased the serum levels of VEGF and TGF-β1. Also, BO promoted the expression of collagen I and increased the ratio in p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR pathways. Our results demonstrate the safety and efficacy of BO and suggest that activation of the PI3K/AKT/mTOR signaling pathway may play an important role in the promotion of wound healing by BO.

Enhancement of osteoporotic bone regeneration by strontium-substituted 45S5 bioglass via time-dependent modulation of autophagy and the Akt/mTOR signaling pathway

2021 ◽  
Vol 9 (16) ◽  
pp. 3489-3501 ◽  
Author(s):  
Xinran Zhang ◽  
Jinjie Cui ◽  
Liming Cheng ◽  
Kaili Lin
Keyword(s):  
Bone Regeneration ◽  
Osteogenic Differentiation ◽  
Signaling Pathway ◽  
Mtor Signaling ◽  
Time Dependent ◽  
Osteoporotic Bone ◽  
Mtor Signaling Pathway ◽  
45S5 Bioglass

Strontium (Sr) promotes osteogenic differentiation and osteoporotic bone regeneration via time-dependent modulation of autophagy and the Akt/mTOR signaling pathway.

scholarly journals Liraglutide Improves Endothelial Function via the mTOR Signaling Pathway

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Han Wu ◽  
Cheng Xiao ◽  
Yiting Zhao ◽  
Hongchao Yin ◽  
Miao Yu
Keyword(s):  
Nitric Oxide ◽  
Endothelial Function ◽  
Western Blot ◽  
Signaling Pathway ◽  
Telomerase Activity ◽  
Mtor Signaling ◽  
Dependent Manner ◽  
Mtor Signaling Pathway ◽  
Akt Phosphorylation ◽  
Akt Activation

Background. Mammalian target of rapamycin (mTOR) is crucial for endothelial function. This study is aimed at assessing whether the glucagon-like peptide-1 (GLP-1) analogue liraglutide has a protective effect on endothelial function via the mTOR signaling pathway. Methods. Human umbilical vein endothelial cells (HUVECs) were administered liraglutide (100 nM) for 0, 10, 30, 60, 720, and 1440 minutes, respectively. Then, the expression and phosphorylation levels of mTOR, mTOR-Raptor complex (mTORC1), and mTOR-Rictor complex (mTORC2) were determined by Western blot and immunoprecipitation, while mTORC1 and mTORC2 expression was blocked by siRNA-Raptor and siRNA-Rictor, respectively. Akt phosphorylation was detected by Western blot. HUVECs were then incubated with liraglutide in the absence or presence of Akt inhibitor IV. Nitric oxide (NO) release was assessed by the nitrate reductase method. Phosphorylated endothelial nitric oxide synthase (eNOS), human telomerase reverse transcriptase (hTERT), and apoptosis-related effectors were assessed for protein levels by Western blot. Telomerase activity was evaluated by ELISA. Results. Sustained mTOR phosphorylation, mTORC2 formation, and mTORC2-dependent Akt phosphorylation were induced by liraglutide. In addition, eNOS phosphorylation, NO production, nuclear hTERT accumulation, and nuclear telomerase activity were enhanced by mTORC2-mediated Akt activation. Liraglutide also showed an antiapoptotic effect by upregulating antiapoptotic proteins and downregulating proapoptotic proteins in an mTORC2-Akt activation-dependent manner. Conclusion. Liraglutide significantly improves endothelial function, at least partially via the mTORC2/Akt signaling pathway.

UPF1 Impacts on mTOR Signaling Pathway and Autophagy in Endometrioid Endometrial Carcinoma

2020 ◽  
Author(s):  
Minfen Zhang ◽  
Hui Chen ◽  
Ping Qin ◽  
Tonghui Cai ◽  
Lingjun Li ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway

Targeting mammalian target of rapamycin: prospects for the treatment of inflammatory bowel diseases

2020 ◽  
Vol 27 ◽  
Author(s):  
Naser-Aldin Lashgari ◽  
Nazanin Momeni Roudsari ◽  
Saeideh Momtaz ◽  
Negar Ghanaatian ◽  
Parichehr Kohansal ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Mammalian Target Of Rapamycin ◽  
Mtor Pathway ◽  
Mtor Signaling ◽  
Target Of Rapamycin ◽  
In Vivo Studies ◽  
Cochrane Library ◽  
Mtor Signaling Pathway ◽  
Inflammatory Bowel

: Inflammatory bowel disease (IBD) is a general term for a group of chronic and progressive disorders. Several cellular and biomolecular pathways are implicated in the pathogenesis of IBD, yet the etiology is unclear. Activation of the mammalian target of rapamycin (mTOR) pathway in the intestinal epithelial cells was also shown to induce inflammation. This review focuses on the inhibition of the mTOR signaling pathway and its potential application in treating IBD. We also provide an overview on plant-derived compounds that are beneficial for the IBD management through modulation of the mTOR pathway. Data were extracted from clinical, in vitro and in vivo studies published in English between 1995 and May 2019, which were collected from PubMed, Google Scholar, Scopus and Cochrane library databases. Results of various studies implied that inhibition of the mTOR signaling pathway downregulates the inflammatory processes and cytokines involved in IBD. In this context, a number of natural products might reverse the pathological features of the disease. Furthermore, mTOR provides a novel drug target for IBD. Comprehensive clinical studies are required to confirm the efficacy of mTOR inhibitors in treating IBD.

Targeting the PI3K/AKT/mTOR Signaling Pathway in Primary Central Nervous System Lymphoma: Current Status and Future Prospects

2020 ◽  
Vol 19 (3) ◽  
pp. 165-173
Author(s):  
Xiaowei Zhang ◽  
Yuanbo Liu
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
B Cell ◽  
Signaling Pathway ◽  
Central Nervous System Lymphoma ◽  
B Cell Lymphoma ◽  
Mtor Signaling ◽  
Mtor Signaling Pathway ◽  
Antitumor Effects ◽  
Term Survival

Primary Central Nervous System Lymphoma (PCNSL) is a rare invasive extranodal non- Hodgkin lymphoma, a vast majority of which is Diffuse Large B-Cell Lymphoma (DLBCL). Although high-dose methotrexate-based immunochemotherapy achieves a high remission rate, the risk of relapse and related death remains a crucial obstruction to long-term survival. Novel agents for the treatment of lymphatic malignancies have significantly broadened the horizons of therapeutic options for PCNSL. The PI3K/AKT/mTOR signaling pathway is one of the most important pathways for Bcell malignancy growth and survival. Novel therapies that target key components of this pathway have shown antitumor effects in many B-cell malignancies, including DLBCL. This review will discuss the aberrant status of the PI3K/AKT/mTOR signaling pathways in PCNSL and the application prospects of inhibitors in hopes of providing alternative clinical therapeutic strategies and improving prognosis.

Exploration of the Effect and Mechanism of ShenQi Compound in a Spontaneous Diabetic Rat Model

2019 ◽  
Vol 19 (5) ◽  
pp. 622-631 ◽  
Author(s):  
Ya Liu ◽  
Jian Kang ◽  
Hong Gao ◽  
Xiyu Zhang ◽  
Jun Chao ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Signaling Pathway ◽  
Rat Model ◽  
Mtor Signaling ◽  
Diabetic Rat ◽  
Gene Microarray ◽  
Mtor Signaling Pathway ◽  
Glucose Fluctuation ◽  
Blood Glucose Fluctuation ◽  
Diabetic Rat Model

Background: Type 2 Diabetes Mellitus (T2DM) is a world-wide metabolic disease with no cure from drugs and treatment. In China, The Traditional Chinese Medicine (TCM) herbal formulations have been used to treat T2DM for centuries. Methods: In this study, we proposed a formula called ShenQi Compound (SQC), which has been used in clinical therapeutics in China for several years. We evaluated the effect of SQC in a spontaneous diabetic rat model (GK rats) by detecting a series of blood indicators and performing histological observations. Meanwhile, the gene microarray and RT-qPCR experiments were used to explore the molecular mechanism of SQC treatment. In addition, western medicine, sitagliptin was employed as a comparison. Results: The results indicated that SQC and sitagliptin could effectively improve the serum lipid (blood Total Cholesterol (TC) and blood Triglycerides (TG)), hormone levels (serum insulin (INS), Glucagon (GC) and Glucagon-Like Peptide-1 (GLP-1)), alleviated the inflammatory response (hypersensitive C-Reactive Protein (hsCRP)), blood glucose fluctuation (Mean Blood Glucose (MBG), standard deviation of blood glucose (SDBG) and Largest Amplitude of plasma Glucose Excursions (LAGE)), pancreatic tissue damage and vascular injury for T2DM. Compared with sitagliptin, SQC achieved a better effect on blood glucose fluctuation (p<0.01). Meanwhile, the gene microarray and RT-qPCR experiments indicated that SQC and sitagliptin may improve the T2DM through affecting the biological functions related to apoptosis and circadian rhythm. Moreover, SQC might be able to influence the mTOR signaling pathway by regulating Pik3r1, Ddit4 expression. Conclusion: All these results indicate that SQC is an effective therapeutic drug on T2DM. Notably, SQC presents an obvious blood glucose fluctuation-preventing ability, which might be derived from the regulation of the mTOR signaling pathway.

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