Animals ; Autophagy ; genetics ; Genes ; Humans ; Neoplasms ; genetics ; pathology ; Signal Transduction ; TOR Serine-Threonine Kinases ; metabolism

Mechanistic target of rapamycin (mTOR) signaling governs important physiological and pathological processes key to cellular life. Loss of mTOR negative regulators and subsequent over-activation of mTOR signaling are major causes underlying epileptic encephalopathy. Our previous studies showed that UBTOR/KIAA1024/MINAR1 acts as a negative regulator of mTOR signaling, but whether UBTOR plays a role in neurological diseases remains largely unknown. We therefore examined a zebrafish model and found that ubtor disruption caused increased spontaneous embryonic movement and neuronal activity in spinal interneurons, as well as the expected hyperactivation of mTOR signaling in early zebrafish embryos. In addition, mutant ubtor larvae showed increased sensitivity to the convulsant pentylenetetrazol, and both the motor activity and the neuronal activity were up-regulated. These phenotypic abnormalities in zebrafish embryos and larvae were rescued by treatment with the mTORC1 inhibitor rapamycin. Taken together, our findings show that ubtor regulates motor hyperactivity and epilepsy-like behaviors by elevating neuronal activity and activating mTOR signaling.
Animals ; Hyperkinesis/genetics* ; Mutation/genetics* ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism* ; Zebrafish/metabolism*

Animals ; Eukaryotic Initiation Factors ; genetics ; metabolism ; Humans ; Phosphorylation ; physiology ; Proteomics ; Ribosomal Proteins ; genetics ; metabolism ; TOR Serine-Threonine Kinases ; genetics ; metabolism

OBJECTIVETo study the association between two single nucleotide polymorphisms (SNP), rs2295080 and rs2536, in mammalian target of rapamycin (mTOR) gene and the susceptibility to pediatric epilepsy.

METHODSA case- control study was performed on 480 children with epilepsy (116 cases of refractory epilepsy) and 503 healthy children. SNP rs2295080 and rs2536 in the mTOR gene were detected by polymerase chain reaction restriction and fragment length polymorphisms (PCR-RFLP). Genotype and allele frequencies of SNP rs2295080 and rs2536 were compared between the children with epilepsy and healthy controls.

RESULTSThere were no significant differences in the genotype and allele frequencies of SNP rs2295080 between the children with epilepsy and healthy controls. There were no significant differences in the genotype frequencies of SNP rs2536 between the two groups either, but the frequency of G allele of SNP rs2536 was higher in children with epilepsy than that in healthy controls (P=0.042, OR=1.344, 95%CI: 1.010-1.789).

CONCLUSIONSSNP rs2536 of mTOR gene may be associated with the risk of pediatric epilepsy.

Epilepsy ; etiology ; genetics ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Polymorphism, Single Nucleotide ; Risk ; TOR Serine-Threonine Kinases ; genetics

This study aims to investigate the role of slient mating-type information regulation 2 homolog 1(SIRT1)/tuberous sclerosis complex 2(TSC2)/mammalian target of rapamycin(mTOR) signaling pathways in the Periplaneta americana extract CⅡ-3-induced senescence of human leukemia K562 cells. K562 cells were cultured in vitro and treated with 0(control), 5, 10, 20, 40, 80, and 160 μg·mL~(-1) of P. americana extract CⅡ-3. Cell counting kit-8(CCK-8) and flow cytometry were employed to examine the proliferation and cell cycle of the K562 cells. Senescence-associated β-galactosidase stain kit(SA-β-gal) was used to detect the positive rate of senescent cells. Mitochondrial membrane potential was detected by flow cytometry. The relative mRNA level of telomerase reverse transcriptase(TERT) was determined by fluorescence quantitative PCR. The mRNA and protein levels of SIRT1, TSC2, and mTOR were determined by fluorescence quantitative PCR and Western blot, respectively. The results showed that CⅡ-3 significantly inhibited the proliferation of K562 cells and the treatment with 80 μg·mL~(-1) CⅡ-3 for 72 h had the highest inhibition rate. Therefore, 80 μg·mL~(-1) CⅡ-3 treatment for 72 h was selected as the standard for subsequent experiments. Compared with the control group, CⅡ-3 increased the proportion of cells arrested in G_0/G_1 phase, decreased the proportion of cells in S phase, increased the positive rate of SA-β-Gal staining, elevated the mitochondrial membrane potential and down-regulated the mRNA expression of TERT. Furthermore, the mRNA expression of SIRT1 and TSC2 was down-regulated, while the mRNA expression of mTOR was up-regulated. The protein expression of SIRT1 and p-TSC2 was down-regulated, while the protein expression of p-mTOR was up-regulated. The results indicated that P. americana extract CⅡ-3 induced the senescence of K562 cells via the SIRT1/mTOR signaling pathway.
Humans ; Animals ; Periplaneta ; Sirtuin 1/genetics* ; K562 Cells ; Signal Transduction ; TOR Serine-Threonine Kinases/genetics* ; RNA, Messenger ; Mammals

Parkinson's disease (PD) is a common age-related neurodegenerative disorder characterized mainly by motor dysfunction resulting in bradykinesia, rigidity, tremor, gait impairment, and postural instability. The classic pathogenic feature of PD is preferential loss of dopaminergic neurons in the substantia nigra. Downregulation of rRNA transcription is one of major mechanisms to maintain cellular homeostasis under stress conditions. Nucleolar stress has emerged as a component of the degenerative process caused by impaired rRNA transcription and altered nucleolar integrity. Recent study has indicated that the response to stress conditions and quality control mechanisms are impaired in PD, and that metabolic stress may be a trigger mechanism for PD. This review aims to present evidence for a role of nucleolar stress in PD and has summarized mechanisms by which nucleolar stress may play a role in the progression of PD.
Cell Nucleolus ; physiology ; Humans ; Parkinson Disease ; etiology ; physiopathology ; RNA, Ribosomal ; genetics ; Signal Transduction ; Stress, Physiological ; TOR Serine-Threonine Kinases ; physiology

β-Elemene is an effective anti-cancer ingredient extracted from the genus Curcuma (Zingiberaceae familiy). In the present study, we demonstrated that β-elemene inhibited the proliferation of colorectal cancer cells and induced cell cycle arrest in the G₂/M phase. In addition, β-elemene induced nuclear chromatin condensation and cell membrane phosphatidylserine eversion, decreased cell mitochondrial membrane potential, and promoted the cleavage of caspase-3, caspase-9 and PARP proteins, indicating apoptosis in colorectal cancer cells. At the same time, β-elemene induced autophagy response, and the treated cells showed autophagic vesicle bilayer membrane structure, which was accompanied by up-regulation of the expression of LC3B and SQSTM1. Furthermore, β-elemene increased ROS levels in colorectal cancer cells, promoted phosphorylation of AMPK protein, and inhibited mTOR protein phosphorylation. In the experiments in vivo, β-elemene inhibited the tumor size and induced apoptosis and autophagy in nude mice. In summary, β-elemene inhibited the occurrence and development of colon cancer xenografts in nude mice, and significantly induced apoptosis and autophagy in colorectal cancer cells in vitro. These effects were associated with regulation of the ROS/AMPK/mTOR signaling. We offered a molecular basis for the development of β-elemene as a promising anti-tumor drug candidate for colorectal cancer.
AMP-Activated Protein Kinases/genetics* ; Animals ; Apoptosis ; Autophagy ; Cell Line, Tumor ; Colorectal Neoplasms/genetics* ; Humans ; Mice ; Mice, Nude ; Reactive Oxygen Species ; Sesquiterpenes ; TOR Serine-Threonine Kinases/genetics*

Eukaryotic translation initiation factor 4B (eIF4B) plays an important role in mRNA translation initiation, cell survival and proliferation in vitro, but the in vivo function is poorly understood. In this study, via various experimental techniques such as hematoxylin-eosin (HE) staining, flow cytometry, Western blotting, and immunohistochemistry, we investigated the role of eIF4B in mouse embryo development using an eIF4B knockout (KO) mouse model and explored the mechanism. We found that the livers, but not lungs, brain, stomach, or pancreas, derived from eIF4B KO mouse embryos displayed severe pathological changes characterized by enhanced apoptosis and necrosis. Accordingly, high expression of cleaved-caspase 3, and excessive activation of mTOR signaling as evidenced by increased expression and phosphorylation of p70S6K and enhanced phosphorylation of 4EBP1, were observed in mouse embryonic fibroblasts and fetal livers from eIF4B KO mice. These results uncover a critical role of eIF4B in mouse embryo development and provide important insights into the biological functions of eIF4B in vivo.
Animals ; Apoptosis/genetics* ; Caspase 3 ; Eosine Yellowish-(YS) ; Eukaryotic Initiation Factors/metabolism* ; Fibroblasts ; Hematoxylin ; Liver/metabolism* ; Mice ; Ribosomal Protein S6 Kinases, 70-kDa/genetics* ; TOR Serine-Threonine Kinases

The present study aimed to investigate the protective role of Shaofu Zhuyu Decoction(SFZY) against endometriosis fibrosis in mice, and decipher the underlying mechanism through the phosphatase and tensin homolog deleted on chromosome ten(PTEN)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) pathway. Eighty-five BALB/c female mice were randomly assigned into a blank group, a model group, high-, medium, and low-dose SFZY(SFZY-H, SFZY-M, and SFZY-L, respectively) groups, and a gestrinone suspension(YT) group. The model of endometriosis was induced by intraperitoneal injection of uterine fragments. The mice in different groups were administrated with corresponding groups by gavage 14 days after modeling, and the blank group and model group with equal volume of distilled water by gavage. The treatment lasted for 14 days. The body weight, paw withdrawal latency caused by heat stimuli, and total weight of dissected ectopic focus were compared between different groups. The pathological changes of the ectopic tissue were observed via hematoxylin-eosin(HE) and Masson staining. Real-time PCR was employed to measure the mRNA levels of α-smooth muscle actin(α-SMA) and collagen type Ⅰ(collagen-Ⅰ) in the ectopic tissue. The protein levels of PTEN, Akt, mTOR, p-Akt, and p-mTOR in the ectopic tissue were determined by Western blot. Compared with the blank group, the modeling first decreased and then increased the body weight of mice, increased the total weight of ectopic focus, and shortened the paw withdrawal latency. Compared with the model group, SFZY and YT increased the body weight, prolonged the paw withdrawal latency, and decreased the weight of ectopic focus. Furthermore, the drug administration, especially SFZY-H and YT(P<0.01), recovered the pathological and reduced the area of collagen deposition. Compared with the blank group, the modeling up-regulated the mRNA levels of α-SMA and collagen-Ⅰ in the ectopic focus, and such up-regulation was attenuated after drug intervention, especially in the SFZY-H and YT groups(P<0.05,P<0.01). Compared with the blank group, the modeling down-regulated the protein level of PTEN and up-regulated the protein levels of Akt, mTOR, p-Akt, and p-mTOR(P<0.01, P<0.001). Drug administration, especially SFZY-H and YT, restored such changes(P<0.01). SFZY may significantly attenuate the focal fibrosis in the mouse model of endometriosis by regulating the PTEN/Akt/mTOR signaling pathway.
Female ; Animals ; Mice ; Humans ; Proto-Oncogene Proteins c-akt/genetics* ; Choristoma ; Endometriosis/genetics* ; TOR Serine-Threonine Kinases/genetics* ; RNA, Messenger ; Signal Transduction ; Body Weight ; Mammals ; PTEN Phosphohydrolase/genetics*

OBJECTIVETo observe the changes of CA916798 gene expression in human lung adenocarcinoma cell A549 and the multidrug-resistant cell line A549/CDDP after blocking the PI3K/AKT/mTOR pathway.

METHODSHuman lung adenocarcinoma cell lines A549 and A549/CDDP were treated with rapamycin and LY294002, and the cell growth changes in response to subsequent cisplatin treatment was observed; RT-PCR was performed to detect CA916798 mRNA expression in the treated cells.

RESULTSBlocking PI3K/AKT/mTOR pathway with rapamycin and LY294002 significantly reduced drug resistance of both A549 and A549/CDDP cells to cisplatin and obviously decreased the expression of CA916798 gene mRNA (P<0.05).

CONCLUSIONCA9167981 gene is located downstream of the PI3K/AKT/mTOR pathway, which might be one of the mechanisms of CA916798 to cause cisplatin resistance in the tumor cells.

Cell Line, Tumor ; Cell Proliferation ; Cisplatin ; pharmacology ; Drug Resistance, Neoplasm ; genetics ; Humans ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; TOR Serine-Threonine Kinases ; metabolism