Research progress on mTOR signaling pathway and regulatory T cell nutrition metabolic regulation mechanism / 细胞与分子免疫学杂志

In the tumor microenvironment, metabolic reprogramming can impact metabolic characteristics of T cells, thus inducing immunosuppression to promote tumor immune escape. The mammalian target of rapamycin (mTOR) signaling pathway plays an important role in regulating diverse functions of various immune cells. This review mainly focuses on the molecular mechanism of mTOR signaling in regulating cellular energy metabolism process, and the activation status of mTOR signaling under different nutritional environments. In addition, it also summarizes the role of the mTOR signaling in regulatory T cell (Tregs) metabolism and function in current studies, and evaluates the potential of mTOR as a clinical immunotherapeutic target and its current application challenges.

Electroacupuncture Promotes Functional Recovery after Facial Nerve Injury in Rats by Regulating Autophagy via GDNF and PI3K/mTOR Signaling Pathway / 中国结合医学杂志

OBJECTIVE@#To explore the mechanism of electroacupuncture (EA) in promoting recovery of the facial function with the involvement of autophagy, glial cell line-derived neurotrophic factor (GDNF), and phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway.@*METHODS@#Seventy-two male Sprague-Dawley rats were randomly allocated into the control, sham-operated, facial nerve injury (FNI), EA, EA+3-methyladenine (3-MA), and EA+GDNF antagonist groups using a random number table, with 12 rats in each group. An FNI rat model was established with facial nerve crushing method. EA intervention was conducted at Dicang (ST 4), Jiache (ST 6), Yifeng (SJ 17), and Hegu (LI 4) acupoints for 2 weeks. The Simone's 10-Point Scale was utilized to monitor the recovery of facial function. The histopathological evaluation of facial nerves was performed using hematoxylin-eosin (HE) staining. The levels of Beclin-1, light chain 3 (LC3), and P62 were detected by immunohistochemistry (IHC), immunofluorescence, and reverse transcription-polymerase chain reaction, respectively. Additionally, IHC was also used to detect the levels of GDNF, Rai, PI3K, and mTOR.@*RESULTS@#The facial functional scores were significantly increased in the EA group than the FNI group (P<0.05 or P<0.01). HE staining showed nerve axons and myelin sheaths, which were destroyed immediately after the injury, were recovered with EA treatment. The expressions of Beclin-1 and LC3 were significantly elevated and the expression of P62 was markedly reduced in FNI rats (P<0.01); however, EA treatment reversed these abnormal changes (P<0.01). Meanwhile, EA stimulation significantly increased the levels of GDNF, Rai, PI3K, and mTOR (P<0.01). After exogenous administration with autophagy inhibitor 3-MA or GDNF antagonist, the repair effect of EA on facial function was attenuated (P<0.05 or P<0.01).@*CONCLUSIONS@#EA could promote the recovery of facial function and repair the facial nerve damages in a rat model of FNI. EA may exert this neuroreparative effect through mediating the release of GDNF, activating the PI3K/mTOR signaling pathway, and further regulating the autophagy of facial nerves.

Hydroxysafflor Yellow A Promotes HaCaT Cell Proliferation and Migration by Regulating HBEGF/EGFR and PI3K/AKT Pathways and Circ_0084443 / 中国结合医学杂志

OBJECTIVE@#To investigate the effect and possible mechanism of hydroxysafflor yellow A (HSYA) on human immortalized keratinocyte cell proliferation and migration.@*METHODS@#HaCaT cells were treated with HSYA. Cell proliferation was detected by the cell counting kit-8 assay, and cell migration was measured using wound healing assay and Transwell migration assay. The mRNA and protein expression levels of heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF), EGF receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), mammalian target of rapamycin (mTOR), and hypoxia-inducible factor-1α (HIF-1α) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA. The expression of circ_0084443 was detected by qRT-PCR.@*RESULTS@#HSYA (800 µmol/L) significantly promoted HaCaT cell proliferation and migration (P<0.05 or P<0.01). It also increased the mRNA and protein expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and increased the phosphorylation levels of PI3K and AKT (P<0.05 or P<0.01). Furthermore, HSYA promoted HaCaT cell proliferation and migration via the HBEGF/EGFR and PI3K/AKT/mTOR signaling pathways (P<0.01). Circ_0084443 attenuated the mRNA expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α (P<0.05). HSYA inhibited the circ_0084443 expression, further antagonized the inhibition of circ_0084443 on HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and promoted the proliferation of circ_0084443-overexpressing HaCaT cells (P<0.05 or P<0.01). However, HSYA could not influence the inhibitory effect of circ_0084443 on HaCaT cell migration (P>0.05).@*CONCLUSION@#HSYA played an accelerative role in HaCaT cell proliferation and migration, which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways, and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.

Cell softness reveals tumorigenic potential via ITGB8/AKT/glycolysis signaling in a mice model of orthotopic bladder cancer / 中华医学杂志(英文版)

BACKGROUND@#Bladder cancer, characterized by a high potential of tumor recurrence, has high lifelong monitoring and treatment costs. To date, tumor cells with intrinsic softness have been identified to function as cancer stem cells in several cancer types. Nonetheless, the existence of soft tumor cells in bladder tumors remains elusive. Thus, our study aimed to develop a micro-barrier microfluidic chip to efficiently isolate deformable tumor cells from distinct types of bladder cancer cells.@*METHODS@#The stiffness of bladder cancer cells was determined by atomic force microscopy (AFM). The modified microfluidic chip was utilized to separate soft cells, and the 3D Matrigel culture system was to maintain the softness of tumor cells. Expression patterns of integrin β8 (ITGB8), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) were determined by Western blotting. Double immunostaining was conducted to examine the interaction between F-actin and tripartite motif containing 59 (TRIM59). The stem-cell-like characteristics of soft cells were explored by colony formation assay and in vivo studies upon xenografted tumor models.@*RESULTS@#Using our newly designed microfluidic approach, we identified a small fraction of soft tumor cells in bladder cancer cells. More importantly, the existence of soft tumor cells was confirmed in clinical human bladder cancer specimens, in which the number of soft tumor cells was associated with tumor relapse. Furthermore, we demonstrated that the biomechanical stimuli arising from 3D Matrigel activated the F-actin/ITGB8/TRIM59/AKT/mTOR/glycolysis pathways to enhance the softness and tumorigenic capacity of tumor cells. Simultaneously, we detected a remarkable up-regulation in ITGB8, TRIM59, and phospho-AKT in clinical bladder recurrent tumors compared with their non-recurrent counterparts.@*CONCLUSIONS@#The ITGB8/TRIM59/AKT/mTOR/glycolysis axis plays a crucial role in modulating tumor softness and stemness. Meanwhile, the soft tumor cells become more sensitive to chemotherapy after stiffening, that offers new insights for hampering tumor progression and recurrence.

Oxidative stress induces autophagy to inhibit the proliferation and apoptosis of human bone marrow mesenchymal stem cells (hBMSCs) / 细胞与分子免疫学杂志

Objective To investigate the effect of H2O2-induced oxidative stress on autophagy and apoptosis of human bone marrow mesenchymal stem cells (hBMSCs). Methods hBMSCs were isolated and cultured. The cells were divided into control group, 3-MA group, H2O2 group, H2O2 combined with 3-MA group. DCFH-DA staining was used to analyze the level of reactive oxygen species (ROS). hBMSCs were treated with 0, 50, 100, 200, 400 μmol/L H2O2, and then the cell viability was detected by CCK-8 assay. The level of autophagy was detected by monodansylcadaverine (MDC) staining and LysoTracker Red staining. The cell apoptosis was detected by flow cytometry. Western blotting was used to detect the expression of beclin 1, mTOR, phosphorylated mTOR (p-mTOR), cleaved caspase-3(c-caspase-3) and caspase-3 proteins. Results Compared with the control group and 3-MA group, ROS level and autophagosomes were increased and the proliferation and apoptosis were decreased in H2O2 group. The protein expression of beclin 1, mTOR, c-caspase-3 was up-regulated, while the p-mTOR was down-regulated. Compared with the 3-MA group, the H2O2 combined with 3-MA group also had an increased ROS level and autophagosomes, but not with significantly increased apoptosis rate; The protein expression of beclin 1, mTOR, c-caspase-3 was up-regulated, and the p-mTOR was down-regulated. Conclusion H2O2 can induce hMSCs to trigger oxidative stress response. It enhances the autophagy and inhibits the proliferation and apoptosis of hBMSCs.

Viral myocarditis serum exosome-derived miR-320 promotes the apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway and targeting phosphatidylinositol 3-kinase regulatory subunit 1 (Pik3r1) / 细胞与分子免疫学杂志

Objective To investigate the effect of viral myocarditis serum exosomal miR-320 on apoptosis of cardiomyocytes and its mechanism. Methods The model of viral myocarditis mice was established by intraperitoneal injection of Coxsackie virus B3. Serum exosomes were extracted by serum exosome extraction kit and co-cultured with cardiomyocytes. The uptake of exosomes by cardiomyocytes was detected by laser confocal microscopy. Cardiomyocytes were transfected with miR-320 inhibitor or mimic, and the expression level of miR-320 was detected by real-time quantitative PCR. Flow cytometry was used to detect cardiomyocyte apoptosis rate, and the expression levels of B cell lymphoma 2 (Bcl2) and Bcl2-related X protein (BAX) were tested by Western blot analysis. The prediction of miR-320 target genes and GO and KEGG enrichment analysis were tested by online database. The relationship between miR-320 and its target gene phosphoinositide-3-kinase regulatory subunit 1(Pik3r1) was examined by luciferase reporter gene. The effect of miR-320 on AKT/mTOR pathway protein was detected by Western blot analysis. Results Viral myocarditis serum exosomes promoted cardiomyocyte apoptosis, and increased the level of BAX while the level of Bcl2 was decreased. miR-320 was significantly up-regulated in myocardial tissue of viral myocarditis mice, and both pri-miR-320 and mature of miR-320 were up-regulated greatly in cardiomyocytes. The level of miR-320 in cardiomyocytes treated with viral myocarditis serum exosomes was significantly up-regulated, while transfection of miR-320 inhibitor counteracted miR-320 overexpression and reduced apoptosis rate caused by exosomes. Pik3r1 is the target gene of miR-320, and its overexpression reversed cardiomyocyte apoptosis induced by miR-320 up-regulation. The overexpression of miR-320 inhibited AKT/mTOR pathway activation. Conclusion Viral myocarditis serum exosome-derived miR-320 promotes apoptosis of mouse cardiomyocytes by inhibiting AKT/mTOR pathway by targeting Pik3r1.

Shaofu Zhuyu Decoction attenuates fibrosis in endometriosis through regulating PTEN/Akt/mTOR signaling pathway / 中国中药杂志

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.

Periplaneta americana extract CⅡ-3 induces senescence of leukemia K562 cells via SIRT1/mTOR signaling pathway / 中国中药杂志

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.

Effect of diosgenin on mTOR/FASN/HIF-1α/VEGFA expression in rats with non-alcoholic fatty liver disease / 中国中药杂志

The present study aimed to investigate the effect of diosgenin on mammalian target of rapamycin(mTOR), fatty acid synthase(FASN), hypoxia inducible factor-1α(HIF-1α), and vascular endothelial growth factor A(VEGFA) expression in liver tissues of rats with non-alcoholic fatty liver disease(NAFLD) and explore the mechanism of diosgenin on lipogenesis and inflammation in NAFLD. Forty male SD rats were divided into a normal group(n=8) fed on the normal diet and an experimental group(n=32) fed on the high-fat diet(HFD) for the induction of the NAFLD model. After modeling, the rats in the experimental group were randomly divided into an HFD group, a low-dose diosgenin group(150 mg·kg~(-1)·d~(-1)), a high-dose diosgenin group(300 mg·kg~(-1)·d~(-1)), and a simvastatin group(4 mg·kg~(-1)·d~(-1)), with eight rats in each group. The drugs were continuously given by gavage for eight weeks. The levels of triglyceride(TG), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-C), alanine transaminase(ALT), and aspartate transaminase(AST) in the serum were detected by the biochemical method. The content of TG and TC in the liver was detected by the enzyme method. Enzyme-linked immunosorbent assay(ELISA) was used to measure interleukin 1β(IL-1β) and tumor necrosis factor α(TNF-α) in the serum. Lipid accumulation in the liver was detected by oil red O staining. Pathological changes of liver tissues were detected by hematoxylin-eosin(HE) staining. The mRNA and protein expression levels of mTOR, FASN, HIF-1α, and VEGFA in the liver of rats were detected by real-time fluorescence-based quantitative polymerase chain reaction(PCR) and Western blot, respectively. Compared with the normal group, the HFD group showed elevated body weight and levels of TG, TC, LDL-C, ALT, AST, IL-1β, and TNF-α(P<0.01), increased lipid accumulation in the liver(P<0.01), obvious liver steatosis, up-regulated mRNA expression levels of mTOR, FASN, HIF-1α, and VEGFA(P<0.01), and increased protein expression levels of p-mTOR, FASN, HIF-1α, and VEGFA(P<0.01). Compared with the HFD group, the groups with drug treatment showed lowered body weight and levels of TG, TC, LDL-C, ALT, AST, IL-1β, and TNF-α(P<0.05, P<0.01), reduced lipid accumulation in the liver(P<0.01), improved liver steatosis, decreased mRNA expression levels of mTOR, FASN, HIF-1α, and VEGFA(P<0.05, P<0.01), and declining protein expression levels of p-mTOR, FASN, HIF-1α, and VEGFA(P<0.01). The therapeutic effect of the high-dose diosgenin group was superior to that of the low-dose diosgenin group and the simvastatin group. Diosgenin may reduce liver lipid synthesis and inflammation and potentiate by down-regulating the mTOR, FASN, HIF-1α, and VEGFA expression, playing an active role in preventing and treating NAFLD.

p53 regulates primordial follicle activation through the mTOR signaling pathway / 生理学报

This paper aimed to investigate the role and potential mechanism of p53 on primordial follicle activation. Firstly, the p53 mRNA expression in the ovary of neonatal mice at 3, 5, 7 and 9 days post-partum (dpp) and the subcellular localization of p53 were detected to confirm the expression pattern of p53. Secondly, 2 dpp and 3 dpp ovaries were cultured with p53 inhibitor Pifithrin-μ (PFT-μ, 5 μmol/L) or equal volume of dimethyl sulfoxide for 3 days. The function of p53 in primordial follicle activation was determined by hematoxylin staining and whole ovary follicle counting. The proliferation of cell was detected by immunohistochemistry. The relative mRNA levels and protein levels of the key molecules involved in the classical pathways associated with the growing follicles were examined by immunofluorescence staining, Western blot and real-time PCR, respectively. Finally, rapamycin (RAP) was used to intervene the mTOR signaling pathway, and ovaries were divided into four groups: Control, RAP (1 μmol/L), PFT-μ (5 μmol/L), PFT-μ (5 μmol/L) + RAP (1 μmol/L) groups. The number of follicles in each group was determined by hematoxylin staining and whole ovary follicle counting. The results showed that the expression of p53 mRNA was decreased with the activation of primordial follicles in physiological condition. p53 was expressed in granulosa cells and oocyte cytoplasm of the primordial follicles and growing follicles, and the expression of p53 in the primordial follicles was higher than that in the growing follicles. Inhibition of p53 promoted follicle activation and reduced the primordial follicle reserve. Inhibition of p53 promoted the proliferation of the granulosa cells and oocytes. The mRNA and protein expression levels of key molecules in the PI3K/AKT signaling pathway including AKT, PTEN, and FOXO3a were not significantly changed after PFT-μ treatment, while the expression of RPS6/p-RPS6, the downstream effectors of the mTOR signaling pathway, was upregulated. Inhibition of both p53 and mTOR blocked p53 inhibition-induced primordial follicle activation. Collectively, these findings suggest that p53 may inhibit primordial follicle activation through the mTOR signaling pathway to maintain the primordial follicle reserve.

In vitro and in vivo anticancer potential and molecular targets of the new colchicine analog IIIM-067 / 中西医结合学报

OBJECTIVE@#The current study evaluated various new colchicine analogs for their anticancer activity and to study the primary mechanism of apoptosis and in vivo antitumor activity of the analogs with selective anticancer properties and minimal toxicity to normal cells.@*METHODS@#Sulforhodamine B (SRB) assay was used to screen various colchicine analogs for their in vitro cytotoxicity. The effect of N-[(7S)-1,2,3-trimethoxy-9-oxo-10-(pyrrolidine-1-yl)5,6,7,9-tetrahydrobenzo[a] heptalene-7-yl] acetamide (IIIM-067) on clonogenicity, apoptotic induction, and invasiveness of A549 cells was determined using a clonogenic assay, scratch assay, and staining with 4',6-diamidino-2-phenylindole (DAPI) and annexin V/propidium iodide. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) levels were observed using fluorescence microscopy. Western blot analysis was used to quantify expression of proteins involved in apoptosis, cell cycle, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling. Pharmacokinetic and in vivo efficacy studies against Ehrlich ascites carcinoma (EAC) and Ehrlich solid tumor models were conducted using Swiss albino mice.@*RESULTS@#IIIM-067 showed potent cytotoxicity and better selectivity than all other colchicine analogs screened in this study. The selective activity of IIIM-067 toward A549 cells was higher among other cancer cell lines, with a selectivity index (SI) value of 2.28. IIIM-067 demonstrated concentration- and time-dependent cytotoxicity against A549 cells with half-maximal inhibitory concentration values of 0.207, 0.150 and 0.106 μmol/L at 24, 48 and 72 h, respectively. It also had reduced toxicity to normal cells (SI > 1) than the parent compound colchicine (SI = 1). IIIM-067 reduced the clonogenic ability of A549 cells in a dose-dependent manner. IIIM-067 enhanced ROS production from 24.6% at 0.05 μmol/L to 82.1% at 0.4 μmol/L and substantially decreased the MMP (100% in control to 5.6% at 0.4 μmol/L). The annexin V-FITC assay demonstrated 78% apoptosis at 0.4 μmol/L. IIIM-067 significantly (P < 0.5) induced the expression of various intrinsic apoptotic pathway proteins, and it differentially regulated the PI3K/AKT/mTOR signaling pathway. Furthermore, IIIM-067 exhibited remarkable in vivo anticancer activity against the murine EAC model, with tumor growth inhibition (TGI) of 67.0% at a dose of 6 mg/kg (i.p.) and a reduced mortality compared to colchicine. IIIM-067 also effectively inhibited the tumor growth in the murine solid tumor model with TGI rates of 48.10%, 55.68% and 44.00% at doses of 5 mg/kg (i.p.), 6 mg/kg (i.p.) and 7 mg/kg (p.o.), respectively.@*CONCLUSION@#IIIM-067 exhibited significant anticancer activity with reduced toxicity both in vitro and in vivo and is a promising anticancer candidate. However, further studies are required in clinical settings to fully understand its potential.

Intermittent heat exposure induces thoracic aorta injury in spontaneously hypertensive rats by activating the AMPK/mTOR/ULK1 pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of different manners of heat exposure on thoracic aorta injury in spontaneously hypertensive rats (SHRs) and explore the underlying mechanism.@*METHODS@#Normal 6 to 7-week-old male SHRs were randomized into control group (cage at room temperature), intermittent heat exposure group (SHR-8 group, exposed to 32 ℃ for 8 h daily for 7 days) and SHR-24 group (with continuous exposure to 32 ℃ for 7 days). After the treatments, the pathologies of the thoracic aorta of the rats were observed with HE staining, and the expressions of Beclin1, LC3B and p62 were detected with Western blotting and immunofluorescence assay; TUNEL staining was used to observe cell apoptosis in the thoracic aorta, and the expressions of caspase-3, Bax, and Bcl-2 were detected using Western blotting. The effects of intraperitoneal injections of 3-MA (an autophagy agonist), rapamycin (an autophagy inhibitor) or compound C 30 min before intermittent heat exposure on the expressions of proteins associated with autophagy, apoptosis and the AMPK/mTOR/ULK1 pathway in the aorta were examined with immunohistochemistry.@*RESULTS@#In SHR-8 group, the rats showed incomplete aortic intima with disordered cell distribution and significantly increased expressions of Beclin1, LC3II/LC3I and Bax, lowered expressions of p62 and Bcl-2, and increased apoptotic cells in the thoracic aorta (P < 0.05). Pretreatment with 3-MA obviously inhibited the expressions of autophagy- and apoptosis-related proteins, whereas rapamycin promoted their expressions. Compared with the control group, the rats in SHR-8 group had significantly down-regulated p-mTOR and up-regulated p-AMPK and p-ULK1 expression of in the aorta; Treatment with compound C obviously lowered the expressions of p-AMPK and p-ULK1 and those of LC3B and Beclin1 as well.@*CONCLUSION@#In SHRs, intermittent heat exposure causes significant pathologies and promotes autophagy and apoptosis in the thoracic aorta possibly by activating the AMPK/mTOR/ULK1 pathway.

Synergistic Antitumor Effect of Everolimus Combined with Gemcitabine on Diffuse Large B-Cell Lymphoma / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of mTOR inhibitors everolimus (EVE) and gemcitabine (GEM) on the proliferation, apoptosis and cell cycle of diffuse large B-cell lymphoma (DLBCL) cell line U2932, and further explore the molecular mechanisms, so as to provide new ideas and experimental basis for the clinical treatment of DLBCL.@*METHODS@#The effect of EVE and GEM on the proliferation of U2932 cells was detected by CCK-8 assay, the IC50 of the two drugs was calculated, and the combination index (CI=) of the two drugs was calculated by CompuSyn software. The effect of EVE and GEM on apoptosis of U2932 cells was detected by flow cytometry with AnnexinV-FITC/PI staining. Flow cytometry with propidium iodide (PI) staining was used to detect the effect of EVE and GEM on the cell cycle of U2932 cells. Western blot assay was used to detect the effects of EVE and GEM on the channel proteins p-mTOR and p-4EBP1, the anti-apoptotic proteins MCL-1 and Survivin, and the cell cycle protein Cyclin D1.@*RESULTS@#Both EVE and GEM could significantly inhitbit the proliferation of U2932 cells in a time- and dose-dependent manner (r=0.465, 0.848; 0.555, 0.796). According to the calculation of CompuSyn software, EVE combined with GEM inhibited the proliferation of U2932 cells at 24, 48 and 72 h with CI=<1, which had a synergistic effect. After treated U2932 cells with 10 nmol/L EVE, 250 nmol/L GEM alone and in combination for 48 h, both EVE and GEM induced apoptosis, and the difference was statistically significant compared with the control group (P<0.05). The apoptosis rate was significantly enhanced after EVE in combination with GEM compared with single-agent (P<0.05). Both EVE and GEM alone and in combination significantly increased the proportion of cells in G1 phase compared with the control group (P<0.05). The proportion of cells in G1 phase was significantly increased when the two drugs were combined (P<0.05). The expression of p-mTOR and effector protein p-4EBP1 was significantly downregulated in the EVE combined with GEM group, the expression of anti-apoptotic proteins MCL-1, Survivin and cell cycle protein cyclin D1 was downregulated too (P<0.05).@*CONCLUSION@#EVE combined with GEM can synergistically inhibit the proliferation of U2932 cells, and the mechanism may be that they can synergistically induce apoptosis by downregulating the expression of MCL-1 and Survivin proteins and block the cell cycle progression by downregulating the expression of Cyclin D1.

Effect and Mechanism of Atorvastatin on Reversing Drug Resistance in Leukemia by Regulating Glycolysis through PTEN/mTOR Pathway / 中国实验血液学杂志

OBJECTIVE@#To investigate the influence and mechanism of atorvastatin on glycolysis of adriamycin resistant acute promyelocytic leukemia (APL) cell line HL-60/ADM.@*METHODS@#HL-60/ADM cells in logarithmic growth phase were treated with different concentrations of atorvastatin, then the cell proliferation activity was measured by CCK-8 assay, the apoptosis was detected by flow cytometry, the glycolytic activity was checked by glucose consumption test, and the protein expressions of PTEN, p-mTOR, PKM2, HK2, P-gp and MRP1 were detected by Western blot. After transfection of PTEN-siRNA into HL-60/ADM cells, the effects of low expression of PTEN on atorvastatin regulating the behaviors of apoptosis and glycolytic metabolism in HL-60/ADM cells were further detected.@*RESULTS@#CCK-8 results showed that atorvastatin could inhibit the proliferation of HL-60/ADM cells in a concentration-dependent and time-dependent manner (r=0.872, r=0.936), and the proliferation activity was inhibited most significantly when treated with 10 μmol/L atorvastatin for 24 h, which was decreased to (32.3±2.18)%. Flow cytometry results showed that atorvastatin induced the apoptosis of HL-60/ADM cells in a concentration-dependent manner (r=0.796), and the apoptosis was induced most notably when treated with 10 μmol/L atorvastatin for 24 h, which reached to (48.78±2.95)%. The results of glucose consumption test showed that atorvastatin significantly inhibited the glycolytic activity of HL-60/ADM cells in a concentration-dependent and time-dependent manner (r=0.915, r=0.748), and this inhibition was most strikingly when treated with 10 μmol/L atorvastatin for 24 h, reducing the relative glucose consumption to (46.53±1.71)%. Western blot indicated that the expressions of p-mTOR, PKM2, HK2, P-gp and MRP1 protein were decreased in a concentration-dependent manner (r=0.737, r=0.695, r=0.829, r=0.781, r=0.632), while the expression of PTEN protein was increased in a concentration-dependent manner (r=0.531), when treated with different concentrations of atorvastatin for 24 h. After PTEN-siRNA transfected into HL-60/ADM cells, it showed that low expression of PTEN had weakened the promoting effect of atorvastatin on apoptosis and inhibitory effect on glycolysis and multidrug resistance.@*CONCLUSION@#Atorvastatin can inhibit the proliferation, glycolysis, and induce apoptosis of HL-60/ADM cells. It may be related to the mechanism of increasing the expression of PTEN, inhibiting mTOR activation, and decreasing the expressions of PKM2 and HK2, thus reverse drug resistance.

S100A10 promotes proliferation and invasion of lung adenocarcinoma cells by activating the Akt-mTOR signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of expression levels of S100 calcium-binding protein A10 (S100A10) in lung adenocarcinoma (LUAD) on patient prognosis and the regulatory role of S100A10 in lung cancer cell proliferation and metastasis.@*METHODS@#Immunohistochemistry was used to detect the expression levels of S100A10 in LUAD and adjacent tissues, and the relationship between S100A10 expression and clinicopathological parameters and prognosis of the patients was statistically analyzed. The lung adenocarcinoma expression dataset in TCGA database was analyzed using gene enrichment analysis (GSEA) to predict the possible regulatory pathways of S100A10 in the development of lung adenocarcinoma. Lactate production and glucose consumption of lung cancer cells with S100A10 knockdown or overexpression were analyzed to assess the level of glycolysis. Western blotting, CCK-8 assay, EdU-594 assay, and Transwell assays were performed to determine the expression level of S100A10 protein, proliferation and invasion ability of lung cancer cells. A549 cells with S100A10 knockdown and H1299 cells with S100A10 overexpression were injected subcutaneously in nude mice, and tumor growth was observed.@*RESULTS@#The expression level of S100A10 was significantly upregulated in LUAD tissues as compared with the adjacent tissues, and an elevated S100A10 expression level was associated with lymph node metastasis, advanced tumor stage and distant organ metastasis (P < 0.05), but not with tumor differentiation or the patients' age or gender (P > 0.05). Survival analysis showed that elevated S100A10 expressions in the tumor tissue was associated with a poor outcome of the patients (P < 0.001). In the lung cancer cells, S100A10 overexpression significantly promoted cell proliferation and invasion in vitro (P < 0.001). GSEA showed that the gene sets of glucose metabolism, glycolysis and mTOR signaling pathway were significantly enriched in high expressions of S100A10. In the tumor-bearing nude mice, S100A10 overexpression significantly promoted tumor growth, while S100A10 knockdown obviously suppressed tumor cell proliferation (P < 0.001).@*CONCLUSION@#S100A10 overexpression promotes glycolysis by activating the Akt-mTOR signaling pathway to promote proliferation and invasion of lung adenocarcinoma cells.

Berberine inhibits autophagy and promotes apoptosis of fibroblast-like synovial cells from rheumatoid arthritis patients through the ROS/mTOR signaling pathway / 南方医科大学学报

OBJECTIVE@#To evaluate the regulatory effect of berberine on autophagy and apoptosis balance of fibroblast-like synoviocytes (FLSs) from patients with in rheumatoid arthritis (RA) and explore the mechanism.@*METHODS@#The inhibitory effect of 10, 20, 30, 40, 50, 60, 70, and 80 μmol/L berberine on RA-FLS proliferation was assessed using CCK-8 method. Annexin V/PI and JC-1 immunofluorescence staining was used to analyze the effect of berberine (30 μmol/L) on apoptosis of 25 ng/mL TNF-α- induced RA-FLSs, and Western blotting was performed to detect the changes in the expression levels of autophagy- and apoptosis-related proteins. The cells were further treated with the autophagy inducer RAPA and the autophagy inhibitor chloroquine to observe the changes in autophagic flow by laser confocal detection of mCherry-EGFP-LC3B. RA-FLSs were treated with the reactive oxygen species (ROS) mimic H2O2 or the ROS inhibitor NAC, and the effects of berberine on ROS, mTOR and p-mTOR levels were observed.@*RESULTS@#The results of CCK-8 assay showed that berberine significantly inhibited the proliferation of RA-FLSs in a time- and concentration-dependent manner. Flow cytometry and JC-1 staining showed that berberine (30 μmol/L) significantly increased apoptosis rate (P < 0.01) and reduced the mitochondrial membrane potential of RA-FLSs (P < 0.05). Berberine treatment obviously decreased the ratios of Bcl-2/Bax (P < 0.05) and LC3B-II/I (P < 0.01) and increased the expression of p62 protein in the cells (P < 0.05). Detection of mCherry-EGFP-LC3B autophagy flow revealed obvious autophagy flow block in berberine-treated RA-FLSs. Berberine significantly reduced the level of ROS in TNF-α-induced RA-FLSs and upregulated the expression level of autophagy-related protein p-mTOR (P < 0.01); this effect was regulated by ROS level, and the combined use of RAPA significantly reduced the pro-apoptotic effect of berberine in RA-FLSs (P < 0.01).@*CONCLUSION@#Berberine can inhibit autophagy and promote apoptosis of RA-FLSs by regulating the ROS-mTOR pathway.

Regulatory Mechanism of Mangiferin Combined with Bortezomib on Malignant Biological Behavior of Burkitt Lymphoma and Its Effect on Expression of CXC Chemokine Receptors / 中国实验血液学杂志

OBJECTIVE@#To analyze the effects of mangiferin combined with bortezomib on the proliferation, invasion, apoptosis and autophagy of human Burkitt lymphoma Raji cells, as well as the expression of CXC chemokine receptors (CXCRs) family, and explore the molecular mechanism between them to provide scientific basis for basic research and clinical work of Burkitt lymphoma.@*METHODS@#Raji cells were intervened with different concentrations of mangiferin and bortezomib alone or in combination, then cell proliferation was detected by CCK-8 assay, cell invasion ability was detected by Transwell chamber method, cell apoptosis was detected by Annexin V/PI double-staining flow cytometry, apoptosis, autophagy and Akt/mTOR pathway protein expression were detected by Western blot, and the expression changes of CXCR family was detected by real-time quantitative PCR (RT-qPCR).@*RESULTS@#Different concentrations of mangiferin intervened Raji cells for different time could inhibit cell viability in a concentration- and time-dependent manner (r =-0.682, r =-0.836). When Raji cells were intervened by combination of mangiferin and bortezomib, compared with single drug group, the proliferation and invasion abilities were significantly decreased, while the apoptosis level was significantly increased (P <0.01). Mangiferin combined with bortezomib could significantly up-regulate the expression of pro-apoptotic protein Bax and down-regulate the expression of anti-apoptotic protein Bcl-2 after intervention in Raji cells. Caspase-3 was also hydrolyzed and activated, and then induced the apoptosis of Raji cells. Mangiferin combined with bortezomib could up-regulate the expression of LC3Ⅱ protein in Raji cells, and the ratio of LC3Ⅱ/LC3Ⅰ in cells was significantly up-regulated compared with single drug or control group (P <0.01). Mangiferin combined with bortezomib could significantly inhibit the phosphorylation levels of Akt and mTOR, inhibit the proliferation and invasion of Raji cells by inhibiting Akt/mTOR pathway, and induce cell autophagy and apoptosis. Mangiferin and bortezomib could down-regulate the expressions of CXCR4 and CXCR7 mRNA after single-agent intervention in Raji cells, and the down-regulations of CXCR4 and CXCR7 mRNA expression were more significant when the two drugs were combined (P <0.01). Mangiferin alone or combined with bortezomib had no significant effect on CXCR5 mRNA expression in Raji cells (P >0.05), while the combination of the two drugs could down-regulate the expression of CXCR3 (P <0.05).@*CONCLUSION@#Mangiferin combined with bortezomib can synergistically inhibit the proliferation and invasion of Raji cells, and induce autophagy and apoptosis. The mechanism may be related to the inhibition of Akt/mTOR signaling pathway, down-regulation of anti-apoptotic protein Bcl-2 and up-regulation of pro-apoptotic protein Bax, and the inhibition of the expression of CXCR family.

Pro-oxidation status of rotator cuff tissue and expression of Beclin-1 and mTOR in patients with rotator cuff injury / 中国骨伤

OBJECTIVE@#To explore pro-oxidative state of rotator cuff tissue and expression levels of Beclin-1 and mam-malian target of rapamycin(mTOR) in patients with acute and chronic rotator cuff injury, and then analyzed relationship between rotator cuff injury and oxidative stress and autophagy.@*METHODS@#Forty patients with rotator cuff injury were seleceted from July 2019 to December 2020, and divided into male chronic injury group, male acute injury group, female chronic injury group, and female acute injury group, 10 patients in each group. All patients were performed rotator cuff repair under arthroscopy. The sample of tendon at the rotator cuff injury site of the patient was taken during operation, and total reactive oxygen species (ROS) and superoxide dismutase(SOD) were detected by detection kit;expression of Beclin-1 and mTOR mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR), and Western-blot was applied to detect protein expression of Beclin-1 and p-mTOR/mTOR.@*RESULTS@#There were no significant difference in expression of ROS, SOD, Beclin-1mRNA and mTOR mRNA between male and female chronic injury groups, and between male and female acute injury groups (P>0.05); ROS, SOD and Beclin-1mRNA in male chronic injury group were higher than those in male chronic injury group, while mTOR mRNAand protein decreased (P<0.05);ROS, SOD and Beclin-1 mRNA in female chronic injury group were up-regulated compared with female acute injury group, while mTOR mRNA was down-regulated (P<0.05).@*CONCLUSION@#Chronic rotator cuff injury is more likely to stimulate the pro-oxidation state of rotator cuff tissue than acute rotator cuff injury, which could up-regulating expression of autophagy factor Beclin-1 and down-regulating expression of mTOR. Therefore, patients with chronic rotator cuff injury may have higher levels of oxidative stress and autophagy.

Eleutheroside B induces apoptosis and autophagy of lung cancer cells by regulating PI3K/Akt/mTOR pathway / 中国中药杂志

This study investigated the effect of eleutheroside B on apoptosis and autophagy of lung cancer A549 and H460 cells and its molecular mechanism. MTT assay was used to detect the cytotoxicity of eleutheroside B at 5, 10, 15, 20, 25, 30, 35, 40, and 45 mmol·L~(-1) on lung cancer cells. Trypan blue exclusion assay was used to detect the effect of eleutheroside B on the survival rate of lung cancer A549 and H460 cells at different time. Colony formation assay was used to detect the effect of eleutheroside B on the proliferation of lung cancer A549 and H460 cells. AO/EB fluorescence double staining and Hoechst 33342 fluorescence staining were used to detect the effect of eleutheroside B on apoptosis of lung cancer A549 and H460 cells, and Western blot was used to detect apoptosis-related proteins to explore the apoptosis-related molecular mechanism. AO fluorescence staining and Western blot were used to detect the expression of autophagic vesicles and autophagy-related proteins P62 and LC3. The results showed that compared with the control group, eleutheroside B inhibited the growth of lung cancer A549 and H460 cells in a concentration-dependent manner. The optimal effect time of eleutheroside B on lung cancer A549 and H460 cells was 24 h, and the optimal concentrations were 28.64 and 22.16 mmol·L~(-1), respectively. Eleutheroside B could inhibit the colony formation of A549 and H460 cells. Compared with the control group, eleutheroside B could promote the formation of apoptotic bodies and induce cell apoptosis, as well as induce the expression of mitochondrial pathway-related proteins. Under the effect of eleutheroside B, the acidic autophagy vacuole in lung cancer cells increased, LC3Ⅱ expression increased, P62 protein expression decreased, and PI3K, p-Akt, and p-mTOR protein expression decreased in the PI3K/Akt/mTOR pathway. Studies have shown that eleutheroside B can inhibit the growth of lung cancer cells, reduce colony formation, induce apoptosis of lung cancer cells through mitochondrial pathway, and induce autophagy. The mechanism may be related to the PI3K/Akt/mTOR pathway.

Protective effect of Shenfu Injection on regulation of autophagy in rats with chronic heart failure based on PI3K/Akt/mTOR pathway / 中国中药杂志

This study aimed to investigate the mechanism and target sites of Shenfu Injection in the intervention of chronic heart fai-lure based on the PI3K/Akt/mTOR autophagy signaling pathway. The chronic heart failure model was induced in rats by subcutaneous injection of isoproterenol. The model rats were randomly divided into model group, Shenfu Injection group, and 3-methyladenine autophagy inhibitor(3-MA) group. A normal group was also set up. After 15 days of administration, cardiac function indexes of the rats were detected by echocardiography. The serum N-terminal pro-B-type natriuretic peptide(NT-proBNP) levels were measured using the ELISA. HE and Masson staining was performed to observe the morphological changes in myocardial tissues, and electron microscopy was used to observe the autophagosomes in myocardial tissues. Western blot was conducted to measure the changes in autophagy-related proteins(LC3 Ⅱ/Ⅰ and p62), PI3K, Akt, mTOR, and phosphorylation levels. The results showed that compared with normal group, model group in rats led to reduced cardiac function, significant activation of cardiac autophagy, increased fibrotic lesions in myocardial tissues, structural disorder of the myocardium, increased autophagosomes, and cytoplasmic vacuolization. Compared with model group, Shenfu Injection group in rats led to cardiac function significantly improved, myocardial fibrosis decreased, and the number of autophagosomes and cytoplasmic vacuolization decreased. The phosphorylation levels of PI3K, Akt, and mTOR were significantly increased(P<0.01). In the 3-MA group, autophagy was inhibited through the activation of the PI3K/Akt/mTOR signaling pathway, resulting in improved cardiac function, reduced myocardial fibrosis, and no significant cytoplasmic vacuolization. The findings suggest that Shenfu Injection can activate the PI3K/Akt/mTOR signaling pathway and inhibit autophagy, thereby improving cardiac function.