Osteopontin promotes gastric cancer progression via phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway.

BACKGROUND: Gastric cancer (GC) is one of the most common malignant tumors. Osteopontin (OPN) is thought to be closely related to the occurrence, metastasis and prognosis of many types of tumors. AIM: To investigate the effects of OPN on the proliferation, invasion and migration of GC cells and its possible mechanism. METHODS: The mRNA and protein expression of OPN in the GC cells were analyzed by real-time quantitative-reverse transcription polymerase chain reaction and western blotting, and observe the effect of varying degree expression OPN on the proliferation and other behaviors of GC. Next, the effects of OPN knockdown on GC cells migration and invasion were examined. The short hairpin RNA (shRNA) and negative control shRNA targeting OPN-shRNA were transfected into the cells according to the manufacturer's instructions. Non transfected cells were classified as control in the identical transfecting process. 24 h after RNA transfection cell proliferation activity was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay, and cell invasiveness and migration were detected by Trans well assay. Meanwhile, the expression of protein kinase B (AKT), matrix metalloproteinase 2 (MMP-2) and vascular endothelial growth factor (VEGF) in the human GC cell lines was detected by reverse transcription polymerase chain reaction and western blotting. RESULTS: The results of this study revealed that OPN mRNA and protein expression levels were highly expressed in SGC-7901 cells. OPN knockdown by specific shRNA noticeably reduced the capabilities of proliferation, invasion and migration of SGC-7901 cells. Moreover, in the experiments of investigating the underlying mechanism, results showed that OPN knockdown could down-regulated the expression of MMP-2 and VEGF, it also decreased the phosphorylation of AKT. Meanwhile, the protein expression levels of MMP-2, VEGF and phosphorylated AKT was noticeable lower than that in control group in the GC cells after they were added to phosphatidylinositol-3-kinase (PI3K) inhibitor (LY294002). CONCLUSION: These results suggested that OPN though PI3K/AKT/mammalian target of rapamycin signal pathway to up-regulate MMP-2 and VEGF expression, which contribute SGC-7901 cells to proliferation, invasion and migration. Thus, our results demonstrate that OPN may serve as a novel prognostic biomarkers as well as a potential therapeutic targets for GC.

Mechanism of melatonin regulation of PI3K/Akt/mTOR signaling in hypothalamus delaying the initiation of puberty in female mice / 解剖学报

Objective To explore the effect of melatonin ( MLT) on the initiation of puberty in female mice and on the expression level of phosphatidylinositol-3-kinases ( PI3K)/protein kinase B ( Akt)/mammalian target of rapamycin (mTOR) signaling pathway in the frypothalamus. Methods Seventy-eight 20-day-old female KM mice were randomly divided into melatonin (MLT) group and normal saline (NS) group, with 39 mice in each group. Starting at 22 days of age, the MLT group was given a subcutaneous injection of 1 mg/kg melatonin and the NS group was given an equal volume of saline. Thirty-two days of age were selected as the sampling point before puberty initiation and 13 mice were executed in each of the two groups, while 37 and 42 days of age were selected as the sampling point after puberty initiation and 13 mice were executed in each of the two groups. Observation of vaginal opening time in mice, weighing of ovaries and uterus to calculate organ indices. HE staining to observe the number of ovarian corpora lutea. The levels of serum luteinizing hormone (LH)were determined by ELISA. The mRNA and protein expression levels of PI3K/Akt/mTOR pathway in frypothalamus were detected by Real-time PCR and Western blotting. Results Compared with the normal saline group, mice in the melatonin group had significantly delayed vaginal opening time ( P < 0. 05 ) , decreased significantly ovarian and uterine volume and index (P<0. 05) , decreased significantly serum LH levels (P<0. 05) , and decreased significantly mRNA and protein expression levels of the frypothalamic PI3K/Akt/mTOR pathway (P<0. 05). Conclusion Melatonin delays puberty initiation in mice by a mechanism that ma)' be related to inhibition of the hypothalamic PI3K/Akt/mTOR signalling pathway.

Long non-coding RNA tumor protein 53 target gene 1 promotes cervical cancer development via regulating microRNA-33a-5p to target forkhead box K2.

Long non-coding RNA tumor protein 53 target gene 1 (TP53TG1) has been unraveled to exert regulatory effects on cancer progression, while the regulatory function of TP53TG1 on cervical cancer (CC) via regulating microRNA (miR)-33a-5p/Forkhead box K2 (FOXK2) axis remains rarely explored. This study aims to unearth the regulatory mechanism of TP53TG1/miR-33a-5p/FOXK2 axis in CC. The CC clinical samples were collected, and CC cells were cultured. TP53TG1, miR-33a-5p and FOXK2 levels were examined in CC tissues and cells. The CC cells were transfected with high- or low-expressed TP53TG1, FOXK2 or miR-33a-5p to determine the changes of CC cell biological activities and the status of phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. The tumorigenesis in nude mice was conducted. The relationship among TP53TG1, miR-33a-5p and FOXK2 was validated. TP53TG1 and FOXK2 expression levels were increased and miR-33a-5p expression level was reduced in CC cells and tissues. The silenced TP53TG1 or FOXK2, or elevated miR-33a-5p decelerated the CC cell development and restrained the activation of PI3K/AKT/mTOR signaling pathway. The depleted FOXK2 or elevated miR-33a-5p reversed the effects of decreased TP53TG1 on CC cell progression. TP53TG1 sponged miR-33a-5p, which targeted FOXK2. The experiment in vivo validated the outcomes of the experiment in vitro. TP53TG1 accelerates the CC development via regulating miR-33a-5p to target FOXK2 with the involvement of PI3K/AKT/mTOR signaling pathway. This study provides novel theory basis and distinct therapeutic targets for CC treatment.

Effect of Huangqisan Pellets on PI3K/Akt/mTOR Signaling Pathway and Autophagy in Kidney of Diabetic Nephropathy Rats / 中国实验方剂学杂志

ObjectiveTo investigate the effect of Huangqisan pellets （HQS） on the phosphatidylinositol-3 kinase/protein kinase B/mammalian target of rapamycin （PI3K/Akt/mTOR） signaling pathway and autophagy in the kidney of diabetic nephropathy （DN） rats. MethodDN rat model was established through high-fat diet combined with intraperitoneal injection of streptozotocin （35 mg·kg-1）. DN rats were randomly assigned into model group， irbesartan （0.027 g·kg-1） group， low-dose HQS （0.54 g·kg-1） group and high-dose HQS （1.08 g·kg-1） group. The levels of 24 h urinary total protein （UTP）， serum albumin （Alb）， serum creatinine （SCr）， urea nitrogen （BUN）， triglyceride （TG） and total cholesterol （TC） were measured after 12 weeks of continuous administration. The pathological changes of renal tissue were observed via hematoxylin-eosin （HE） staining. The expression of podocyte split diaphragm proteins nephrin and podocin in the renal tissue were detected by immunohistochemistry. The protein levels and phosphorylation of key proteins in PI3K/Akt/mTOR signaling pathway， as well as the expression of yeast Atg6 homolog （Beclin1） and microtubule-associated protein 1 light chain 3 （LC3） in the renal tissue were analyzed by Western blot. ResultCompared with the control group， the model group showcased increased 24 h UTP， SCr， BUN， TG， and TC levels and decreased Alb level （P<0.01）. After modeling， the rats showed granulosity of epithelial cells of renal tubules， thickening of capillary basement membrane， proliferation of mesangial cells， and sclerosis of glomerulus. Furthermore， modeling down-regulated the expression of nephrin and podocin in the podocyte hiatus of glomerulus （P<0.01） as well as the protein levels of p-PI3K， p-Akt， and p-mTOR and the autophagy markers LC3 and Beclin1 in renal tissue （P<0.01）. Compared with model group， irbesartan and HQS decreased the 24 h UTP， Cr， BUN， TG， and TC levels， increased the Alb level， and alleviated the pathological damage of kidney. Moreover， they up-regulated the expression of Nephrin and Podocin in the podocyte hiatus of glomerulus， as well as the protein levels of p-PI3K， p-Akt， p-mTOR， LC3， and Beclin1 in renal tissue （P<0.05， P<0.01）. ConclusionHQS may inhibit the PI3K/Akt/mTOR signaling pathway to enhance podocyte autophagy and protect the glomerulus， thus slowing down the development of DN.

Effects of silicon dioxide exposure on lipid deposition and PI3K/AKT/mTOR signaling pathway in MLE-12 cells / 环境与职业医学

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.

Scutellarin regulates osteoarthritis in vitro by inhibiting the PI3K/AKT/mTOR signaling pathway.

Osteoarthritis (OA) is a highly prevalent disease worldwide that causes disability and diminishes the quality of life of affected individuals. The disease is characterized by cartilage destruction, increased inflammatory responses and cholesterol metabolic disorder. Scutellarin is the major active ingredient extracted from Erigeron breviscapus, and it has been demonstrated to possess various pharmacological functions in the treatment of the disease. However, its effects on OA are complex. The present study investigated whether scutellarin can mediate the release of inflammatory cytokines, the expression of collagen- and cholesterol-related proteins, and regulate the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway in a cell model of OA. Interleukin (IL)-1ß was used to stimulate OA in SW1353 cells in vitro. The primary methods used were ELISA and western blotting, which were carried out to examine the effects of scutellarin on the cell model of OA. It was found that scutellarin increased the expression of collagen II and SRY-box 9, whereas it suppressed the expression of matrix metalloproteinase 13. In addition, scutellarin downregulated the expression levels of cholesterol 25-hydroxylase and cytochrome P450 family 7 subfamily B polypeptide 1, but upregulated the expression of apolipoprotein A-1 and adenosine triphosphate-binding cassette transporter A1. The IL-1ß-induced increase in the expression of IL-6 was decreased by treatment with scutellarin; however, scutellarin did not alter the expression of C-reactive protein and tumor necrosis factor-α. The protein expression levels of AKT, phosphorylated (p)-AKT, mTOR and p-mTOR in the PI3K/AKT/mTOR signaling pathway were decreased in the IL-1ß-induced SW1353 cells following scutellarin treatment. Overall, the findings of the present study demonstrated that scutellarin regulated OA in vitro by inhibiting the PI3K/AKT/mTOR signaling pathway.

Effect of Sishenwan on PI3K/Akt/mTOR Signal Pathway in Colonic Tissue of Rats with Ulcerative Colitis Model of Spleen Kidney Yang Deficiency / 中国实验方剂学杂志

Objective:To discuss the effect of Sishenwan on phosphatidylinositol-3 kinase/protein kinase B/mammalian target of rapamycin（PI3K/Akt/mTOR） signaling pathway related genes and proteins in colon tissue and interleukin-1<italic>β</italic>（IL-1<italic>β</italic>） and interleukin-10（IL-10） expression levels in serum of ulcerative colitis （UC） model rats with spleen kidney Yang deficiency. Method:The 120 SPF Wistar rats were randomly divided into normal group and model group after 7 days of adaptive feeding in SPF laboratory. The model group were given dinitrobenzene sulfonate （DNBS）/ethanol solution enema+hydrocortisone subcutaneously injection+senna leaf gavage to establish UC model of spleen kidney yang deficiency. The rats who successfully established the model were randomly divided into five groups：model group， mesalazine （0.36 g·kg^-1） group， and Sishenwan high， medium and low dose （3.2，1.6，0.8 g·kg^-1） groups， the volume of which was 10 mL·kg^-1. The model group and the blank group were given distilled water of the same volume. Once a day for 21 days. Observe the general conditions of the rats daily， and record the weight， fecal traits and occult blood of the mice for disease activity index （DAI） scoring.Take the rat colon tissue to observe the gross morphology and colon injury， and score the colon mucosal injury index （CMDI）. Hematoxylin-eosin （HE） staining was used to observe pathological changes. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）was used to detect the expression level of PI3K， Akt， mTOR mRNA in colon tissue. The levels of IL-1<italic>β</italic> and IL-10 in serum were detected by enzyme-linked immunosorbent assay （ELISA）. Western blot was used to detect the expression level of PI3K， phosphorylation （p）-PI3K， Akt， p-Akt， mTOR， p-mTOR protein in colon tissue. Result:Compared with blank group， the general survival status of the rats in model group was relatively poor， the DAI score and the CMDI index were significantly increased （<italic>P<</italic>0.01）. The intestinal mucosa partially disappears， the glands disappear， and a large number of inflammatory cells infiltrate and gather in the mucosal layer and the base layer in the pathological sections of the model group. The expression levels of PI3K， Akt， and mTOR mRNA were significantly increased （<italic>P</italic><0.01）. The IL-1<italic>β</italic> content was significantly increased and the IL-10 content was significantly decreased （<italic>P</italic><0.01）. The expression levels of p-PI3K，p-Akt and p-mTOR protein were significantly increased （<italic>P</italic><0.01）. Compared with the model group， the DAI scores of Sishenwan high and medium dose groups and mesalazine group decreased （<italic>P</italic><0.05）. The CMDI index of mesalazine group and the high， middle and low dose groups of Sishenwan was significantly reduced （<italic>P</italic><0.01）. Pathological sections of rats showed that the inflammatory cells in the drug group decreased， and the mucosal layer structure returned to normal to varying degrees. The mesalazine group and the Sishenwan medium-dose group had the best effects， and the mucosal structure was close to the blank control group. The expression levels of PI3K， Akt， mTOR mRNA in the high and medium dose groups of Sishenwan， mesalazine group and Akt mRNA in low dose group of Sishenwan were significantly reduced （<italic>P</italic><0.05，<italic>P</italic><0.01）. The expression levels of PI3K and mTOR mRNA in low-dose group of Sishenwan decreased， but the difference was not statistically significant. The IL-1<italic>β</italic> content was significantly reduced and the IL-10 content was significantly increased in high， medium dose groups of Sishenwan and mesalazine groups （<italic>P</italic><0.05，<italic>P</italic><0.01）. The level of IL-1<italic>β</italic> decreased and the level of IL-10 increased in the low-dose group of Sishenwan， but the difference was not statistically significant. The expression levels of p-PI3K， p-Akt and p-mTOR protein in the high， medium， and low dose groups of Sishenwan and mesalazine group decreased to varying degrees， and the differences were statistically significant（<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Sishenwan has the effect of improving the general condition and intestinal mucosal damage of ulcerative colitis model rats with spleen and kidney Yang deficiency. The mechanism may be related to the inhibition of PI3K/Akt/mTOR signaling pathway.

[Effects of Quercetin on Autophagy and Phosphatidylinositol 3-kinase/Protein Kinase B/Mammalian Target of Rapamycin Signaling Pathway in Human Prostate Cancer PC-3 Cells].

Objective To investigate the effects of quercetin on cell viability,apoptosis,autophagy,and phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR)signaling pathway in human prostate cell carcinoma PC-3 cells.Methods PC-3 cells were cultured in vitro,and cell viability was detected by CCK-8.Apoptosis was detected by TUNEL staining.Autophagy vesicle was observed by acridine orange staining.Autophagosomes was observed by GFP-LC3 plasmid transfection analysis.Expressions of autophagy-related protein microtubule associated protein 1 light chain 3 fusion protein(LC3)and Beclin-1 and PI3K/Akt/mTOR signaling pathway protein were detected by Western blot analysis.Results Quercetin inhibited cell viability in a dose-time dependent manner and induced apoptosis.Quercetin increased the number of autophagy vesicles and autophagosomes in PC-3 cells.Quercetin increased the expressions of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 in PC-3 cells and decreased the expression of phosphorylated-PI3K,phosphorylated-Akt and phosphorylated-mTOR.Conclusion Quercetin may induce autophagy by inactivating PI3K/Akt/mTOR signaling pathway in PC-3 cells.

Qishen Huanwu capsule reduces pirarubicin-induced cardiotoxicity in rats by activating the PI3K/Akt/mTOR pathway.

BACKGROUND: One of the common adverse reactions to anthracyclines, a group of chemotherapeutics, is cardiotoxicity. Cancer patients receiving anthracycline-based chemotherapeutic regimens often discontinue treatment due to cardiotoxicity. How to prevent and reduce the cardiotoxicity of anthracyclines is one of the hot topics in the field of onco-cardiology. Traditional Chinese medicine can reduce the toxic side effects of chemotherapeutics. The present study aimed to investigate the protective effect of Qishen Huanwu capsule (QSHWC) on pirarubicin (THP)-induced myocardial injury in rats and the underlying mechanisms. METHODS: Forty-eight male Sprague-Dawley (SD) rats were randomly divided into six groups: control group, THP, low-dose QSHWC, moderate-dose QSHWC, high-dose QSHWC, and LY294002 [phosphatidylinositol 3-kinase (PI3K) inhibitor] (n=8 each). Echocardiographic examination was performed to examine heart structure and function. Hematoxylin and eosin (HE) staining was conducted to examine histopathological changes in myocardial tissue. Immunofluorescence staining was carried out to examine the expression of the autophagosome-specific marker protein microtubule-associated protein 1 light chain 3 (LC3). Western blot was performed to analyze the expression of LC3-I, LC3-II, PI3K, phosphorylated (p)-PI3K, protein kinase B (Akt), p-Akt, mammalian target of rapamycin (mTOR), and p-mTOR. RESULTS: Compared with the control group, the THP group had a higher left ventricular end-systolic diameter (LVESD), lower left ventricular ejection fraction (LVEF), lower left ventricular fractional shortening (LVFS), and inferior heart function. In addition, compared with the control group, the THP group had significantly higher LC3 protein expression, a significantly higher LC3-II/LC3-I ratio (P<0.05), and significantly lower p-PI3K, p-Akt, and p-mTOR (P<0.05). QSHWC attenuated the THP-induced decline in heart function, downregulated LC3 protein in rat myocardial tissue, decreased the LC3-II/LC3-I ratio, and increased p-PI3K, p-Akt, and p-mTOR. In the LY294002 group, the above effects of QSHWC were reversed. CONCLUSIONS: QSHWC alleviated THP-induced myocardial injury. The underlying mechanism was related to the activation of the PI3K/Akt/mTOR pathway and the mitigation of the excessive autophagy of cardiomyocytes caused by THP.

Toxoplasma gondii excreted-secreted antigens suppress Foxp3 via PI3K-AKT-mTOR signaling pathway.

Toxoplasma gondii excreted-secreted antigens (ESA) cause spontaneous abortion or fetal teratogenesis during the pregnancy in mice, especially in the early stage. Those adverse pregnancy outcomes are due to the deficit in regulatory T cells (Tregs). Forkhead box P3 (Foxp3), a critical transcription factor, modulates Tregs differentiation and its function. Besides, phosphatidylinositol 3-kinase-protein kinase B-mammalian target of rapamycin (PI3K-AKT-mTOR) signaling network is implicated in interfering with Foxp3 induction. We previously demonstrated that ESA diminished the number of Tregs and inhibited its function. And ESA suppressed Foxp3 expression via the attenuation of transforming growth factor ß RII/Smad2/Smad3/Smad4 pathway. The current study aimed to investigate whether the PI3K-AKT-mTOR signaling network is involved in Foxp3 downregulation induced by ESA. We found that ESA upregulated PI3K, P-AKT, mTOR, and P-mTOR. Knockdown of PI3K cooperated with ESA to restore Foxp3 expression mediated by ESA. This suppressive role of ESA on Foxp3 expression was abrogated by AKT inhibitor. In addition, neutralization of Toll-like receptor 4 could restore the expression of Foxp3, PI3K, and its downstream effectors induced by ESA. Collectively, the findings indicated that ESA inhibited Foxp3 expression via the upregulation of PI3K-AKT-mTOR signaling pathway.

Influence of Phosphatidylinositol-3-Kinase/Protein Kinase B-Mammalian Target of Rapamycin Signaling Pathway on the Neuropathic Pain Complicated by Nucleoside Reverse Transcriptase Inhibitors for the Treatment of HIV Infection.

BACKGROUND: Nucleoside reverse transcriptase inhibitors (NRTIs) are the earliest and most commonly used anti-human immunodeficiency virus drugs and play an important role in high active antiretroviral therapy. However, NRTI drug therapy can cause peripheral neuropathic pain. In this study, we aimed to investigate the mechanisms of rapamycin on the pain sensitization of model mice by in vivo experiments to explore the effect of mammalian target of rapamycin (mTOR) in the pathogenesis of neuropathic pain caused by NRTIs. METHODS: Male Kun Ming (KM) mice weighing 20-22 g were divided into control, 2 mg/kg rapamycin, 12 mg/kg stavudine, and CMC-Na groups. Drugs were orally administered to mice for 42 consecutive days. The von Frey filament detection and thermal pain tests were conducted on day 7, 14, 21, 28, 35, and 42 after drug administration. After the last behavioral tests, immunohistochemistry and western blotting assay were used for the measurement of mTOR and other biomarkers. Multivariate analysis of variance was used. RESULTS: The beneficial effects of rapamycin on neuropathic pain were attributed to a reduction in mammalian target of rapamycin sensitive complex 1 (mTORC1)-positive cells (70.80 ± 2.41 vs. 112.30 ± 5.66, F = 34.36, P < 0.01) and mTORC1 activity in the mouse spinal cord. Mechanistic studies revealed that Protein Kinase B (Akt)/mTOR signaling pathway blockade with rapamycin prevented the phosphorylation of mTORC1 in stavudine-intoxicated mice (0.72 ± 0.04 vs. 0.86 ± 0.03, F = 4.24, P = 0.045), as well as decreased the expression of phospho-p70S6K (0.47 ± 0.01 vs. 0.68 ± 0.03, F = 6.01, P = 0.022) and phospho-4EBP1 (0.90 ± 0.04 vs. 0.94 ± 0.06, F = 0.28, P = 0.646). CONCLUSIONS: Taken together, these results suggest that stavudine elevates the expression and activity of mTORC1 in the spinal cord through activating the Akt/mTOR signaling pathway. The data also provide evidence that rapamycin might be useful for the treatment of peripheral neuropathic pain.

Influence of Phosphatidylinositol-3-Kinase/Protein Kinase B-Mammalian Target of Rapamycin Signaling Pathway on the Neuropathic Pain Complicated by Nucleoside Reverse Transcriptase Inhibitors for the Treatment of HIV Infection / 中华医学杂志(英文版)

Background@#Nucleoside reverse transcriptase inhibitors (NRTIs) are the earliest and most commonly used anti-human immunodeficiency virus drugs and play an important role in high active antiretroviral therapy. However, NRTI drug therapy can cause peripheral neuropathic pain. In this study, we aimed to investigate the mechanisms of rapamycin on the pain sensitization of model mice by in vivo experiments to explore the effect of mammalian target of rapamycin (mTOR) in the pathogenesis of neuropathic pain caused by NRTIs.@*Methods@#Male Kun Ming (KM) mice weighing 20-22 g were divided into control, 2 mg/kg rapamycin, 12 mg/kg stavudine, and CMC-Na groups. Drugs were orally administered to mice for 42 consecutive days. The von Frey filament detection and thermal pain tests were conducted on day 7, 14, 21, 28, 35, and 42 after drug administration. After the last behavioral tests, immunohistochemistry and western blotting assay were used for the measurement of mTOR and other biomarkers. Multivariate analysis of variance was used.@*Results@#The beneficial effects of rapamycin on neuropathic pain were attributed to a reduction in mammalian target of rapamycin sensitive complex 1 (mTORC1)-positive cells (70.80 ± 2.41 vs. 112.30 ± 5.66, F = 34.36, P < 0.01) and mTORC1 activity in the mouse spinal cord. Mechanistic studies revealed that Protein Kinase B (Akt)/mTOR signaling pathway blockade with rapamycin prevented the phosphorylation of mTORC1 in stavudine-intoxicated mice (0.72 ± 0.04 vs. 0.86 ± 0.03, F = 4.24, P = 0.045), as well as decreased the expression of phospho-p70S6K (0.47 ± 0.01 vs. 0.68 ± 0.03, F = 6.01, P = 0.022) and phospho-4EBP1 (0.90 ± 0.04 vs. 0.94 ± 0.06, F = 0.28, P = 0.646).@*Conclusions@#Taken together, these results suggest that stavudine elevates the expression and activity of mTORC1 in the spinal cord through activating the Akt/mTOR signaling pathway. The data also provide evidence that rapamycin might be useful for the treatment of peripheral neuropathic pain.

ß-hydroxyisovaleryl-shikonin induces human cervical cancer cell apoptosis via PI3K/AKT/mTOR signaling.

The present study aimed to investigate the inhibitory ability of ß-hydroxyisovaleryl-shikonin (ß-HIVS) on the proliferation of human cervical cancer HeLa cells and to identify the mechanism of this effect. The HeLa cells were treated with ß-HIVS and the inhibition of cell growth was detected by an MTT assay. Flow cytometry was performed to analyze the apoptosis rate and cell cycle distribution of HeLa cells. Reverse transcription-polymerase chain reaction and western blot analysis were used to examine the expression of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway proteins. The results revealed that ß-HIVS inhibited HeLa cell proliferation in a dose- and time-dependent manner. With the administration of increasing concentrations of ß-HIVS, the apoptotic rate of HeLa cells was also increased. The cell cycle was slightly arrested at the S phase, with ~6% of cells in this phase, subsequent to treatment with 10 µM ß-HIVS. In addition, ß-HIVS markedly reduced the expression levels of PI3K, AKT, mTOR and 70-kDa ribosomal protein S6 kinase in HeLa cells. ß-HIVS promoted cervical cancer cell apoptosis by inhibiting the PI3K/AKT/mTOR signaling pathway and suppressing downstream gene expression. The present study is expected to lead to the development of molecular targeted therapy for this signaling pathway as a novel method of cervical cancer treatment.

Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway and epilepsy / 中华实用儿科临床杂志

Study of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway has been becoming more and more popular.This pathway widely exists in kinds of cells of human being.As one main anti-apoptic and enhancing survival pathway in cells, it plays an important role in cellular growth (increased cell size), proliferation (increased cell number), apoptosis, cell survival and migration.At the same time,the pathway regulates many major cellular processes and is implicated in an increasing number of pathological conditions, including cancer, obesity, type 2 diabetes, and neurodegeneration disease, epilepsy.In recent years,many studies have shown that the dysfunction of PI3K/Akt/mTOR signaling pathway can lead to neurodevelopmental disease.Loss of tuberous sclerosis complex (TSC)1/2 or phosphatase ad tensin homologue deleted on chromosome 10 (PTEN), or environmental stimuli such as inflammation, epilepsy, or hypoxia may stimulate mTOR-dependent protein synthesis,resulting in a host of cellular, structural, and physiological responses that culminate in clinical symptoms.Study the role of mTOR signaling pathway in early-onset epileptic encephalopathy, discuss the intervention and therapy in early-onset epileptic encephalopathy have important clinical meanings.In this article, the components, physiological functions,information were elucidated relative to the PI3 K/Akt/mTOR signaling pathway, and the interaction of the signaling pathway and epilepsy was discussed.