BACKGROUND Monopolar spindle-binding protein 3B(MOB3B)functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.AIM To investigate the role of MOB3B in colorecta...BACKGROUND Monopolar spindle-binding protein 3B(MOB3B)functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.AIM To investigate the role of MOB3B in colorectal cancer(CRC).METHODS This study collected 102 CRC tissue samples for immunohistochemical detection of MOB3B expression for association with CRC prognosis.After overexpression and knockdown of MOB3B expression were induced in CRC cell lines,changes in cell viability,migration,invasion,and gene expression were assayed.Tumor cell autophagy was detected using transmission electron microscopy,while nude mouse xenograft experiments were performed to confirm the in-vitro results.RESULTS MOB3B expression was reduced in CRC vs normal tissues and loss of MOB3B expression was associated with poor CRC prognosis.Overexpression of MOB3B protein in vitro attenuated the cell viability as well as the migration and invasion capacities of CRC cells,whereas knockdown of MOB3B expression had the opposite effects in CRC cells.At the molecular level,microtubule-associated protein light chain 3 II/I expression was elevated,whereas the expression of matrix metalloproteinase(MMP)2,MMP9,sequestosome 1,and phosphorylated mechanistic target of rapamycin kinase(mTOR)was downregulated in MOB3B-overexpressing RKO cells.In contrast,the opposite results were observed in tumor cells with MOB3B knockdown.The nude mouse data confirmed these in-vitro findings,i.e.,MOB3B expression suppressed CRC cell xenograft growth,whereas knockdown of MOB3B expression promoted the growth of CRC cell xenografts.CONCLUSION Loss of MOB3B expression promotes CRC development and malignant behaviors,suggesting a potential tumor suppressive role of MOB3B in CRC by inhibition of mTOR/autophagy signaling.展开更多
BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPI...BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPINH1 in colorectal cancer(CRC)remain largely elusive.AIM To investigate the effects of SERPINH1 on CRC cells and its specific mechanism.METHODS Quantitative real-time polymerase chain reaction,western blotting analysis,The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues.A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in CRC.RESULTS SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues,manifested at both mRNA and protein tiers.Elevated SERPINH1 levels correlated closely with advanced T stage,lymph node involvement,and distant metastasis,exhibiting a significant association with poorer overall survival among CRC patients.Subsequent investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation,invasion,and migration in vitro,while conversely,SERPINH1 knockdown elicited the opposite effects.Gene set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle regulation.Our findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation,thereby facilitating CRC cell invasion and migration.CONCLUSION These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC,potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.展开更多
Mammalian target of rapamycin, also known as me-chanistic target of rapamycin(m TOR) is a protein kinase that belongs to the PI3K/AKT/m TOR signaling pathway, which is involved in several fundamental cellular function...Mammalian target of rapamycin, also known as me-chanistic target of rapamycin(m TOR) is a protein kinase that belongs to the PI3K/AKT/m TOR signaling pathway, which is involved in several fundamental cellular functions such as cell growth, proliferation, and survival. This protein and its associated pathway have been implicated in cancer development and the regulation of immune responses, including the rejection response generated following allograft transplantation. Inhibitors of m TOR(m TORi) such as rapamycin and its derivative everolimus are potent immunosuppressive drugs that both maintain similar rates of efficacy and could optimize the renal function and diminish the side effects compared with calcineurin inhibitors. These drugs are used in solid-organ transplantationtoinduceimmunosuppression while also promoting the expansion of CD4+CD25+FOXP3+ regulatory T-cells that could favor a scenery of immu-nological tolerance. In this review, we describe the mechanisms by which inhibitors of m TOR induce sup-pression by regulation of these pathways at different levels of the immune response. In addition, we par-ticularly emphasize about the main methods that are used to assess the potency of immunosuppressive drugs, highlighting the studies carried out about immunosuppressive potency of inhibitors of m TOR.展开更多
BACKGROUND The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin(PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills(XHP) a...BACKGROUND The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin(PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills(XHP) are a traditional Chinese preparation with antitumour properties. They inhibit the growth of breast cancer, glioma, and other tumours by regulating the PI3K/Akt/mTOR signalling pathway. However, the effects and mechanisms of action of XHP in hepatocellular carcinoma(HCC) remain unclear. Regulation of the PI3K/Akt/mTOR signalling pathway effectively inhibits the progression of HCC. However, no study has focused on the XHPassociated PI3K/Akt/mTOR signalling pathway. Therefore, we hypothesized that XHP might play a role in inhibiting HCC through the PI3K/Akt/mTOR signalling pathway.AIM To confirm the effect of XHP on HCC and the possible mechanisms involved.METHODS The chemical constituents and active components of XHP were analysed using ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS). Cellbased experiments and in vivo xenograft tumour experiments were utilized to evaluate the effect of XHP on HCC tumorigenesis. First, SMMC-7721 cells were incubated with different concentrations of XHP(0, 0.3125, 0.625, 1.25, and 2.5 mg/mL) for 12 h, 24 h and 48 h. Cell viability was assessed using the CCK-8 assay, followed by an assessment of cell migration using a wound healing assay.Second, the effect of XHP on the apoptosis of SMMC-7721 cells was evaluated. SMMC-7721 cells were stained with fluorescein isothiocyanate and annexin V/propidium iodide. The number of apoptotic cells and cell cycle distribution were measured using flow cytometry. The cleaved protein and mRNA expression levels of caspase-3 and caspase-9 were detected using Western blotting and quantitative reverse-transcription polymerase chain reaction(RT-qPCR), respectively.Third, Western blotting and RT–qPCR were performed to confirm the effects of XHP on the protein and mRNA expression of components of the PI3K/Akt/mTOR signalling pathway.Finally, the effects of XHP on the tumorigenesis of subcutaneous hepatocellular tumours in nude mice were assessed.RESULTS The following 12 compounds were identified in XHP using high-resolution mass spectrometry:Valine, 4-gingerol, myrrhone, ricinoleic acid, glycocholic acid, curzerenone, 11-keto-β-boswellic acid, oleic acid, germacrone, 3-acetyl-9,11-dehydro-β-boswellic acid, 5β-androstane-3,17-dione, and 3-acetyl-11-keto-β-boswellic acid. The cell viability assay results showed that treatment with 0.625mg/mL XHP extract decreased HCC cell viability after 12 h, and the effects were dose-and timedependent. The results of the cell scratch assay showed that the migration of HCC cells was significantly inhibited in a time-dependent manner by the administration of XHP extract(0.625mg/mL). Moreover, XHP significantly inhibited cell migration and resulted in cell cycle arrest and apoptosis. Furthermore, XHP downregulated the PI3K/Akt/mTOR signalling pathway, which activated apoptosis executioner proteins(e.g., caspase-9 and caspase-3). The inhibitory effects of XHP on HCC cell growth were determined in vivo by analysing the tumour xenograft volumes and weights.CONCLUSION XHP inhibited HCC cell growth and migration by stimulating apoptosis via the downregulation of the PI3K/Akt/mTOR signalling pathway, followed by the activation of caspase-9 and caspase-3.Our findings clarified that the antitumour effects of XHP on HCC cells are mediated by the PI3K/Akt/mTOR signalling pathway, revealing that XHP may be a potential complementary therapy for HCC.展开更多
多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸...多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)及哺乳动物雷帕霉素靶蛋白(Mammalian target of rapamycin,mTOR)作为细胞能量感受器是其中两个关键靶点。二者在PCOS各个发病部位包括下丘脑-垂体-卵巢轴、子宫内膜、脂肪与骨骼肌中发挥重要的调节作用,通过影响细胞自噬、氧化应激、炎症、线粒体功能、葡萄糖摄取等,促进卵泡的发育和成熟,改善胰岛素抵抗。近年来,中医药因其成分多样、靶点众多等优势广泛应用于临床,研究人员已对PCOS的发病以及中药治疗及改善PCOS的机制进行了大量研究,结果提示AMPK与mTOR相关通路在其中发挥关键作用。通过总结中药干预AMPK与mTOR及其相关通路治疗PCOS的研究结果,为临床治疗及基础研究提供参考。展开更多
The global increase in lifespan noted not only in developed nations,but also in large developing countries parallels an observed increase in a significant number of noncommunicable diseases,most notable neurodegenerat...The global increase in lifespan noted not only in developed nations,but also in large developing countries parallels an observed increase in a significant number of noncommunicable diseases,most notable neurodegenerative disorders.Neurodegenerative disorders present a number of challenges for treatment options that do not resolve disease progression.Furthermore,it is believed by the year 2030,the services required to treat cognitive disorders in the United States alone will exceed$2 trillion annually.Mammalian forkhead transcription factors,silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae),the mechanistic target of rapamycin,and the pathways of autophagy and apoptosis offer exciting avenues to address these challenges by focusing upon core cellular mechanisms that may significantly impact nervous system disease.These pathways are intimately linked such as through cell signaling pathways involving protein kinase B and can foster,sometimes in conjunction with trophic factors,enhanced neuronal survival,reduction in toxic intracellular accumulations,and mitochondrial stability.Feedback mechanisms among these pathways also exist that can oversee reparative processes in the nervous system.However,mammalian forkhead transcription factors,silent mating type information regulation 2 homolog 1,mechanistic target of rapamycin,and autophagy can lead to cellular demise under some scenarios that may be dependent upon the precise cellular environment,warranting future studies to effectively translate these core pathways into successful clinical treatment strategies for neurodegenerative disorders.展开更多
Hepatocellular carcinoma(HCC) is one of the leading causes of cancer-related death worldwide. It is associated with a poor prognosis and has limited treatment options. Sorafenib, a multi-targeted kinase inhibitor, is ...Hepatocellular carcinoma(HCC) is one of the leading causes of cancer-related death worldwide. It is associated with a poor prognosis and has limited treatment options. Sorafenib, a multi-targeted kinase inhibitor, is the only available systemic agent for treatment of HCC that improves overall survival for patients with advanced stage disease; unfortunately, an effective second-line agent for the treatment of progressive or sorafenib-resistant HCC has yet to be identified. This review focuses on components of the mammalian target of rapamycin(mTOR) pathway, its role in HCC pathogenesis, and dual mTOR inhibition as a therapeutic option with potential efficacy in advanced HCC. There are several important upstream and downstream signals in the mTOR pathway, and alternative tumor-promoting pathways are known to exist beyond mTORC1 inhibition in HCC. This review analyzes the relationships of the upstream and downstream regulators of mTORC1 and mTORC2 signaling; it also provides a comprehensive global picture of the interaction between mTORC1 and mTORC2 which demonstrates the pre-clinical relevance of the mTOR pathway in HCC pathogenesis and progression. Finally, it provides scientific rationale for dual mTORC1 and mTORC2 inhibition in the treatment of HCC. Clinical trials utilizing mTORC1 inhibitors and dual mTOR inhibitors in HCC are discussed as well. The mTOR pathway is comprised of two main components, mTORC1 and mTORC2; each has a unique role in the pathogenesis and progression of HCC. In phase Ⅲ studies, mTORC1 inhibitors demonstrate anti-tumor ac-tivity in advanced HCC, but dual mTOR(mTORC1 and mTORC2) inhibition has greater therapeutic potential in HCC treatment which warrants further clinical investigation.展开更多
BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing ...BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing osteogenesis.In the bone marrow(BM)niche,bone mesenchymal stem cells(BMSCs)are exposed to a hypoxic environment.Recently,a few studies have demonstrated that hypoxiainducible factor 2alpha(HIF-2α)is involved in BMSC osteogenic differentiation,but the molecular mechanism involved has not been determined.AIM To investigate the effect of HIF-2αon the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells(HSCs)in the BM niche on the progression of OP.METHODS Mice with BMSC-specific HIF-2αknockout(Prx1-Cre;Hif-2αfl/fl mice)were used for in vivo experiments.Bone quantification was performed on mice of two genotypes with three interventions:Bilateral ovariectomy,semilethal irradiation,and dexamethasone treatment.Moreover,the hematopoietic function of HSCs in the BM niche was compared between the two mouse genotypes.In vitro,the HIF-2αagonist roxadustat and the HIF-2αinhibitor PT2399 were used to investigate the function of HIF-2αin BMSC osteogenic and adipogenic differentiation.Finally,we investigated the effect of HIF-2αon BMSCs via treatment with the mechanistic target of rapamycin(mTOR)agonist MHY1485 and the mTOR inhibitor rapamycin.RESULTS The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention conditions.In vitro,Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2αagonist roxadustat,and after 7 d of BMSC adipogenic differentiation,the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased;in addition,after 14 d of osteogenic differentiation,BMSCs treated with roxadustat exhibited increased expression of osteogenesis-related genes.The opposite effects were shown for mouse BMSCs treated with the HIF-2αinhibitor PT2399.The mTOR inhibitor rapamycin was used to confirm that HIF-2αregulated BMSC osteogenic and adipogenic differentiation by inhibiting the mTOR pathway.Consequently,there was no significant difference in the hematopoietic function of HSCs between Prx1-Cre;Hif-2αfl/fl and Hif-2αfl/fl mice.CONCLUSION Our study showed that inhibition of HIF-2αdecreases bone mass by inhibiting the osteogenic differentiation and increasing the adipogenic differentiation of BMSCs through inhibition of mTOR signaling in the BM niche.展开更多
BACKGROUND 3,6-dichlorobenzo[b]thiophene-2-carboxylic acid(BT2)is a benzothiophene carboxylate derivative that can suppress the catabolism of branched-chain amino acid(BCAA)-associated mammalian target of rapamycin co...BACKGROUND 3,6-dichlorobenzo[b]thiophene-2-carboxylic acid(BT2)is a benzothiophene carboxylate derivative that can suppress the catabolism of branched-chain amino acid(BCAA)-associated mammalian target of rapamycin complex 1(mTORC1)activation.Previous studies have demonstrated the therapeutic effects of BT2 on arthritis,liver cancer,and kidney injury.However,the effects of BT2 on ulcerative colitis(UC)are unknown.AIM To investigate the anti-UC effects of BT2 and the underlying mechanism.METHODS Mouse UC models were created through the administration of 3.5%dextran sodium sulfate(DSS)for 7 d.The mice in the treated groups were administered salazosulfapyridine(300 mg/kg)or BT2(20 mg/kg)orally from day 1 to day 7.At the end of the study,all of the mice were sacrificed,and colon tissues were removed for hematoxylin and eosin staining,immunoblot analyses,and immunohistochemical assays.Cytokine levels were measured by flow cytometry.The contents of BCAAs including valine,leucine,and isoleucine,in mouse serum were detected by liquid chromatography-tandem mass spectrometry,and the abundance of intestinal flora was analyzed by 16S ribosomal DNA sequencing.RESULTS Our results revealed that BT2 significantly ameliorated the inflammatory symptoms and pathological damage induced by DSS in mice.BT2 also reduced the production of the proinflammatory cytokines interleukin 6(IL-6),IL-9,and IL-2 and increased the anti-inflammatory cytokine IL-10 level.In addition,BT2 notably improved BCAA catabolism and suppressed mTORC1 activation and cyclooxygenase-2 expression in the colon tissues of UC mice.Furthermore,highthroughput sequencing revealed that BT2 restored the gut microbial abundance and diversity in mice with colitis.Compared with the DSS group,BT2 treatment increased the ratio of Firmicutes to Bacteroidetes and decreased the abundance of Enterobacteriaceae and Escherichia-Shigella.CONCLUSION Our results indicated that BT2 significantly ameliorated DSS-induced UC and that the latent mechanism involved the suppression of BCAA-associated mTORC1 activation and modulation of the intestinal flora.展开更多
Enhancing hepatic gluconeogenesis is one of the main modes of meeting the glucose requirement of dairy cows.This study attempted to determine whether the gluconeogenesis precursor propionate had an effect on the expre...Enhancing hepatic gluconeogenesis is one of the main modes of meeting the glucose requirement of dairy cows.This study attempted to determine whether the gluconeogenesis precursor propionate had an effect on the expression of the main genes involved in gluconeogenesis in calf hepatocytes and elucidate the associated mechanisms.Calf hepatocytes were obtained from 5 healthy calves(1 d old;30to 40 kg)and exposed to 0-,1-,2.5-,or 5-mM sodium propionate(NaP),which is known to promote the expression of genes involved in the gluconeogenesis pathway,including fructose 1,6-bisphosphatase,phosphoenolpyruvate carboxykinase,and glucose-6-phosphatase.With regard to the underlying mechanism,propionate promoted the expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha,hepatocyte nuclear factor 4,and forkhead box O1(transcription factors that regulate the expression of hepatic gluconeogenic genes)by promoting mammalian target of rapamycin complex 1(mTORC1),but inhibiting mTORC2 activity(P<0.01).We also established a model of palmitic acid(PA)-induced hepatic injury in calf hepatocytes and found that PA could inhibit the gluconeogenic capacity of calf hepatocytes by suppressing the expression of gluconeogenic genes,inhibiting m TORC1,and promoting the activity of m TORC2(P<0.01).In contrast,NaP provided protection to calf hepatocytes by counteracting the inhibitory effect of PA on the gluconeogenic capacity of calf hepatocytes(P<0.05).Collectively,these findings indicate that NaP enhances the gluconeogenic capacity of calf hepatocytes by regulating the mTOR pathway activity.Thus,in addition to improving the glucose production potential,propionate may have therapeutic potential for the treatment of hepatic injury in dairy cows.展开更多
基金Supported by National Natural Science Foundation of China,No.81760516Natural Science Foundation of Guangxi,China,No.2019GXNSFAA185030+1 种基金Self-Financed Scientific Research Projects of Guangxi Zhuang Autonomous Region Health and Family Planning Commission,China,No.Z20181003Guangxi Medical University Youth Science Fund Project,China,No.GXMUYSF202221.
文摘BACKGROUND Monopolar spindle-binding protein 3B(MOB3B)functions as a signal transducer and altered MOB3B expression is associated with the development of human cancers.AIM To investigate the role of MOB3B in colorectal cancer(CRC).METHODS This study collected 102 CRC tissue samples for immunohistochemical detection of MOB3B expression for association with CRC prognosis.After overexpression and knockdown of MOB3B expression were induced in CRC cell lines,changes in cell viability,migration,invasion,and gene expression were assayed.Tumor cell autophagy was detected using transmission electron microscopy,while nude mouse xenograft experiments were performed to confirm the in-vitro results.RESULTS MOB3B expression was reduced in CRC vs normal tissues and loss of MOB3B expression was associated with poor CRC prognosis.Overexpression of MOB3B protein in vitro attenuated the cell viability as well as the migration and invasion capacities of CRC cells,whereas knockdown of MOB3B expression had the opposite effects in CRC cells.At the molecular level,microtubule-associated protein light chain 3 II/I expression was elevated,whereas the expression of matrix metalloproteinase(MMP)2,MMP9,sequestosome 1,and phosphorylated mechanistic target of rapamycin kinase(mTOR)was downregulated in MOB3B-overexpressing RKO cells.In contrast,the opposite results were observed in tumor cells with MOB3B knockdown.The nude mouse data confirmed these in-vitro findings,i.e.,MOB3B expression suppressed CRC cell xenograft growth,whereas knockdown of MOB3B expression promoted the growth of CRC cell xenografts.CONCLUSION Loss of MOB3B expression promotes CRC development and malignant behaviors,suggesting a potential tumor suppressive role of MOB3B in CRC by inhibition of mTOR/autophagy signaling.
基金Supported by Ruian Natural Science Foundation,No.MS2021008.
文摘BACKGROUND Serpin peptidase inhibitor clade H member 1(SERPINH1)was initially recognized as an oncogene implicated in various human malignancies.Nevertheless,the clinical relevance and functional implications of SERPINH1 in colorectal cancer(CRC)remain largely elusive.AIM To investigate the effects of SERPINH1 on CRC cells and its specific mechanism.METHODS Quantitative real-time polymerase chain reaction,western blotting analysis,The Cancer Genome Atlas data mining and immunohistochemistry were employed to examine SERPINH1 expression in CRC cell lines and tissues.A series of in-vitro assays were performed to demonstrate the function of SERPINH1 and its possible mechanisms in CRC.RESULTS SERPINH1 demonstrated elevated expression levels in both CRC cells and tissues,manifested at both mRNA and protein tiers.Elevated SERPINH1 levels correlated closely with advanced T stage,lymph node involvement,and distant metastasis,exhibiting a significant association with poorer overall survival among CRC patients.Subsequent investigations unveiled that SERPINH1 overexpression notably bolstered CRC cell proliferation,invasion,and migration in vitro,while conversely,SERPINH1 knockdown elicited the opposite effects.Gene set enrichment analysis underscored a correlation between SERPINH1 upregulation and genes associated with cell cycle regulation.Our findings underscored the capacity of heightened SERPINH1 levels to expedite G1/S phase cell cycle progression via phosphatidylinositol 3-kinase/AKT/mechanistic target of rapamycin pathway activation,thereby facilitating CRC cell invasion and migration.CONCLUSION These findings imply a crucial involvement of SERPINH1 in the advancement and escalation of CRC,potentially positioning it as a novel candidate for prognostic assessment and therapeutic intervention in CRC management.
基金Supported by Novartis Espana and by grant to Pons JA as Principal Investigator from Instituto Salud Carlos III,No.PI12/02042
文摘Mammalian target of rapamycin, also known as me-chanistic target of rapamycin(m TOR) is a protein kinase that belongs to the PI3K/AKT/m TOR signaling pathway, which is involved in several fundamental cellular functions such as cell growth, proliferation, and survival. This protein and its associated pathway have been implicated in cancer development and the regulation of immune responses, including the rejection response generated following allograft transplantation. Inhibitors of m TOR(m TORi) such as rapamycin and its derivative everolimus are potent immunosuppressive drugs that both maintain similar rates of efficacy and could optimize the renal function and diminish the side effects compared with calcineurin inhibitors. These drugs are used in solid-organ transplantationtoinduceimmunosuppression while also promoting the expansion of CD4+CD25+FOXP3+ regulatory T-cells that could favor a scenery of immu-nological tolerance. In this review, we describe the mechanisms by which inhibitors of m TOR induce sup-pression by regulation of these pathways at different levels of the immune response. In addition, we par-ticularly emphasize about the main methods that are used to assess the potency of immunosuppressive drugs, highlighting the studies carried out about immunosuppressive potency of inhibitors of m TOR.
基金Supported by National Natural Science Foundation of China, No. U20A20408 and No. 82074450Natural Science Foundation of Hunan Province, No. 2020JJ4066+4 种基金Hunan Province"Domestic First-class Cultivation Discipline"Integrated Traditional Chinese and Western Medicine Open Fund Project, No. 2020ZXYJH34 and No. 2020ZXYJH35Hunan Graduate Scientific Research Innovation Project, No. QL20210173 and No. CX20210730Hunan Province Science and Technology Innovation Talents Plan College Students Science and Technology Innovation and Entrepreneurship Project, No. 2020RC1004Guangzhou Health Science and Technology Project, No. 20221A011102Hunan Traditional Chinese Medicine Scientific Research Project, No. 202101
文摘BACKGROUND The phosphoinositide 3-kinase/protein kinase-B/mechanistic target of rapamycin(PI3K/Akt/mTOR) signalling pathway is crucial for cell survival, differentiation, apoptosis and metabolism. Xihuang pills(XHP) are a traditional Chinese preparation with antitumour properties. They inhibit the growth of breast cancer, glioma, and other tumours by regulating the PI3K/Akt/mTOR signalling pathway. However, the effects and mechanisms of action of XHP in hepatocellular carcinoma(HCC) remain unclear. Regulation of the PI3K/Akt/mTOR signalling pathway effectively inhibits the progression of HCC. However, no study has focused on the XHPassociated PI3K/Akt/mTOR signalling pathway. Therefore, we hypothesized that XHP might play a role in inhibiting HCC through the PI3K/Akt/mTOR signalling pathway.AIM To confirm the effect of XHP on HCC and the possible mechanisms involved.METHODS The chemical constituents and active components of XHP were analysed using ultra-performance liquid chromatography-quadrupole time of flight mass spectrometry(UPLC-Q-TOF-MS). Cellbased experiments and in vivo xenograft tumour experiments were utilized to evaluate the effect of XHP on HCC tumorigenesis. First, SMMC-7721 cells were incubated with different concentrations of XHP(0, 0.3125, 0.625, 1.25, and 2.5 mg/mL) for 12 h, 24 h and 48 h. Cell viability was assessed using the CCK-8 assay, followed by an assessment of cell migration using a wound healing assay.Second, the effect of XHP on the apoptosis of SMMC-7721 cells was evaluated. SMMC-7721 cells were stained with fluorescein isothiocyanate and annexin V/propidium iodide. The number of apoptotic cells and cell cycle distribution were measured using flow cytometry. The cleaved protein and mRNA expression levels of caspase-3 and caspase-9 were detected using Western blotting and quantitative reverse-transcription polymerase chain reaction(RT-qPCR), respectively.Third, Western blotting and RT–qPCR were performed to confirm the effects of XHP on the protein and mRNA expression of components of the PI3K/Akt/mTOR signalling pathway.Finally, the effects of XHP on the tumorigenesis of subcutaneous hepatocellular tumours in nude mice were assessed.RESULTS The following 12 compounds were identified in XHP using high-resolution mass spectrometry:Valine, 4-gingerol, myrrhone, ricinoleic acid, glycocholic acid, curzerenone, 11-keto-β-boswellic acid, oleic acid, germacrone, 3-acetyl-9,11-dehydro-β-boswellic acid, 5β-androstane-3,17-dione, and 3-acetyl-11-keto-β-boswellic acid. The cell viability assay results showed that treatment with 0.625mg/mL XHP extract decreased HCC cell viability after 12 h, and the effects were dose-and timedependent. The results of the cell scratch assay showed that the migration of HCC cells was significantly inhibited in a time-dependent manner by the administration of XHP extract(0.625mg/mL). Moreover, XHP significantly inhibited cell migration and resulted in cell cycle arrest and apoptosis. Furthermore, XHP downregulated the PI3K/Akt/mTOR signalling pathway, which activated apoptosis executioner proteins(e.g., caspase-9 and caspase-3). The inhibitory effects of XHP on HCC cell growth were determined in vivo by analysing the tumour xenograft volumes and weights.CONCLUSION XHP inhibited HCC cell growth and migration by stimulating apoptosis via the downregulation of the PI3K/Akt/mTOR signalling pathway, followed by the activation of caspase-9 and caspase-3.Our findings clarified that the antitumour effects of XHP on HCC cells are mediated by the PI3K/Akt/mTOR signalling pathway, revealing that XHP may be a potential complementary therapy for HCC.
文摘多囊卵巢综合征(Polycystic ovary syndrome,PCOS)是一组生殖内分泌代谢紊乱的综合征,临床以稀发排卵、高雄激素体征、胰岛素抵抗为主要特征,其中育龄期发病率高,对女性生育力造成严重不良影响。PCOS的发生发展涉及多种信号通路,腺苷酸活化蛋白激酶(AMP-activated protein kinase,AMPK)及哺乳动物雷帕霉素靶蛋白(Mammalian target of rapamycin,mTOR)作为细胞能量感受器是其中两个关键靶点。二者在PCOS各个发病部位包括下丘脑-垂体-卵巢轴、子宫内膜、脂肪与骨骼肌中发挥重要的调节作用,通过影响细胞自噬、氧化应激、炎症、线粒体功能、葡萄糖摄取等,促进卵泡的发育和成熟,改善胰岛素抵抗。近年来,中医药因其成分多样、靶点众多等优势广泛应用于临床,研究人员已对PCOS的发病以及中药治疗及改善PCOS的机制进行了大量研究,结果提示AMPK与mTOR相关通路在其中发挥关键作用。通过总结中药干预AMPK与mTOR及其相关通路治疗PCOS的研究结果,为临床治疗及基础研究提供参考。
基金supported by American Diabetes AssociationAmerican Heart Association+3 种基金National Institutes of Health-National Institute of Environmental Health SciencesNational Institutes of Health-National Institute on AgingNational Institutes of Health-National Institute of Neurological DisordersNational Institutes of Health-American Recovery and Reinvestment(to KM)。
文摘The global increase in lifespan noted not only in developed nations,but also in large developing countries parallels an observed increase in a significant number of noncommunicable diseases,most notable neurodegenerative disorders.Neurodegenerative disorders present a number of challenges for treatment options that do not resolve disease progression.Furthermore,it is believed by the year 2030,the services required to treat cognitive disorders in the United States alone will exceed$2 trillion annually.Mammalian forkhead transcription factors,silent mating type information regulation 2 homolog 1(Saccharomyces cerevisiae),the mechanistic target of rapamycin,and the pathways of autophagy and apoptosis offer exciting avenues to address these challenges by focusing upon core cellular mechanisms that may significantly impact nervous system disease.These pathways are intimately linked such as through cell signaling pathways involving protein kinase B and can foster,sometimes in conjunction with trophic factors,enhanced neuronal survival,reduction in toxic intracellular accumulations,and mitochondrial stability.Feedback mechanisms among these pathways also exist that can oversee reparative processes in the nervous system.However,mammalian forkhead transcription factors,silent mating type information regulation 2 homolog 1,mechanistic target of rapamycin,and autophagy can lead to cellular demise under some scenarios that may be dependent upon the precise cellular environment,warranting future studies to effectively translate these core pathways into successful clinical treatment strategies for neurodegenerative disorders.
文摘Hepatocellular carcinoma(HCC) is one of the leading causes of cancer-related death worldwide. It is associated with a poor prognosis and has limited treatment options. Sorafenib, a multi-targeted kinase inhibitor, is the only available systemic agent for treatment of HCC that improves overall survival for patients with advanced stage disease; unfortunately, an effective second-line agent for the treatment of progressive or sorafenib-resistant HCC has yet to be identified. This review focuses on components of the mammalian target of rapamycin(mTOR) pathway, its role in HCC pathogenesis, and dual mTOR inhibition as a therapeutic option with potential efficacy in advanced HCC. There are several important upstream and downstream signals in the mTOR pathway, and alternative tumor-promoting pathways are known to exist beyond mTORC1 inhibition in HCC. This review analyzes the relationships of the upstream and downstream regulators of mTORC1 and mTORC2 signaling; it also provides a comprehensive global picture of the interaction between mTORC1 and mTORC2 which demonstrates the pre-clinical relevance of the mTOR pathway in HCC pathogenesis and progression. Finally, it provides scientific rationale for dual mTORC1 and mTORC2 inhibition in the treatment of HCC. Clinical trials utilizing mTORC1 inhibitors and dual mTOR inhibitors in HCC are discussed as well. The mTOR pathway is comprised of two main components, mTORC1 and mTORC2; each has a unique role in the pathogenesis and progression of HCC. In phase Ⅲ studies, mTORC1 inhibitors demonstrate anti-tumor ac-tivity in advanced HCC, but dual mTOR(mTORC1 and mTORC2) inhibition has greater therapeutic potential in HCC treatment which warrants further clinical investigation.
基金Supported by Basic and Applied Basic Research Foundation of Guangdong Province,No.2020A1515010123 and No.2021A1515010695Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province,No.2019A030317011.
文摘BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing osteogenesis.In the bone marrow(BM)niche,bone mesenchymal stem cells(BMSCs)are exposed to a hypoxic environment.Recently,a few studies have demonstrated that hypoxiainducible factor 2alpha(HIF-2α)is involved in BMSC osteogenic differentiation,but the molecular mechanism involved has not been determined.AIM To investigate the effect of HIF-2αon the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells(HSCs)in the BM niche on the progression of OP.METHODS Mice with BMSC-specific HIF-2αknockout(Prx1-Cre;Hif-2αfl/fl mice)were used for in vivo experiments.Bone quantification was performed on mice of two genotypes with three interventions:Bilateral ovariectomy,semilethal irradiation,and dexamethasone treatment.Moreover,the hematopoietic function of HSCs in the BM niche was compared between the two mouse genotypes.In vitro,the HIF-2αagonist roxadustat and the HIF-2αinhibitor PT2399 were used to investigate the function of HIF-2αin BMSC osteogenic and adipogenic differentiation.Finally,we investigated the effect of HIF-2αon BMSCs via treatment with the mechanistic target of rapamycin(mTOR)agonist MHY1485 and the mTOR inhibitor rapamycin.RESULTS The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention conditions.In vitro,Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2αagonist roxadustat,and after 7 d of BMSC adipogenic differentiation,the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased;in addition,after 14 d of osteogenic differentiation,BMSCs treated with roxadustat exhibited increased expression of osteogenesis-related genes.The opposite effects were shown for mouse BMSCs treated with the HIF-2αinhibitor PT2399.The mTOR inhibitor rapamycin was used to confirm that HIF-2αregulated BMSC osteogenic and adipogenic differentiation by inhibiting the mTOR pathway.Consequently,there was no significant difference in the hematopoietic function of HSCs between Prx1-Cre;Hif-2αfl/fl and Hif-2αfl/fl mice.CONCLUSION Our study showed that inhibition of HIF-2αdecreases bone mass by inhibiting the osteogenic differentiation and increasing the adipogenic differentiation of BMSCs through inhibition of mTOR signaling in the BM niche.
基金Supported by National Natural Science Foundation of ChinaNo. 82074241+1 种基金Project of Jiangsu Province Hospital of Traditional Chinese Medicine Peak TalentNo. y2021rc36
文摘BACKGROUND 3,6-dichlorobenzo[b]thiophene-2-carboxylic acid(BT2)is a benzothiophene carboxylate derivative that can suppress the catabolism of branched-chain amino acid(BCAA)-associated mammalian target of rapamycin complex 1(mTORC1)activation.Previous studies have demonstrated the therapeutic effects of BT2 on arthritis,liver cancer,and kidney injury.However,the effects of BT2 on ulcerative colitis(UC)are unknown.AIM To investigate the anti-UC effects of BT2 and the underlying mechanism.METHODS Mouse UC models were created through the administration of 3.5%dextran sodium sulfate(DSS)for 7 d.The mice in the treated groups were administered salazosulfapyridine(300 mg/kg)or BT2(20 mg/kg)orally from day 1 to day 7.At the end of the study,all of the mice were sacrificed,and colon tissues were removed for hematoxylin and eosin staining,immunoblot analyses,and immunohistochemical assays.Cytokine levels were measured by flow cytometry.The contents of BCAAs including valine,leucine,and isoleucine,in mouse serum were detected by liquid chromatography-tandem mass spectrometry,and the abundance of intestinal flora was analyzed by 16S ribosomal DNA sequencing.RESULTS Our results revealed that BT2 significantly ameliorated the inflammatory symptoms and pathological damage induced by DSS in mice.BT2 also reduced the production of the proinflammatory cytokines interleukin 6(IL-6),IL-9,and IL-2 and increased the anti-inflammatory cytokine IL-10 level.In addition,BT2 notably improved BCAA catabolism and suppressed mTORC1 activation and cyclooxygenase-2 expression in the colon tissues of UC mice.Furthermore,highthroughput sequencing revealed that BT2 restored the gut microbial abundance and diversity in mice with colitis.Compared with the DSS group,BT2 treatment increased the ratio of Firmicutes to Bacteroidetes and decreased the abundance of Enterobacteriaceae and Escherichia-Shigella.CONCLUSION Our results indicated that BT2 significantly ameliorated DSS-induced UC and that the latent mechanism involved the suppression of BCAA-associated mTORC1 activation and modulation of the intestinal flora.
基金supported by the National Natural Science Foundation of China(grant numbers 32070782,32072761,32100578)the Guangdong Basic and Applied Basic Research Foundation(grant number 2021A1515220036).
文摘Enhancing hepatic gluconeogenesis is one of the main modes of meeting the glucose requirement of dairy cows.This study attempted to determine whether the gluconeogenesis precursor propionate had an effect on the expression of the main genes involved in gluconeogenesis in calf hepatocytes and elucidate the associated mechanisms.Calf hepatocytes were obtained from 5 healthy calves(1 d old;30to 40 kg)and exposed to 0-,1-,2.5-,or 5-mM sodium propionate(NaP),which is known to promote the expression of genes involved in the gluconeogenesis pathway,including fructose 1,6-bisphosphatase,phosphoenolpyruvate carboxykinase,and glucose-6-phosphatase.With regard to the underlying mechanism,propionate promoted the expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha,hepatocyte nuclear factor 4,and forkhead box O1(transcription factors that regulate the expression of hepatic gluconeogenic genes)by promoting mammalian target of rapamycin complex 1(mTORC1),but inhibiting mTORC2 activity(P<0.01).We also established a model of palmitic acid(PA)-induced hepatic injury in calf hepatocytes and found that PA could inhibit the gluconeogenic capacity of calf hepatocytes by suppressing the expression of gluconeogenic genes,inhibiting m TORC1,and promoting the activity of m TORC2(P<0.01).In contrast,NaP provided protection to calf hepatocytes by counteracting the inhibitory effect of PA on the gluconeogenic capacity of calf hepatocytes(P<0.05).Collectively,these findings indicate that NaP enhances the gluconeogenic capacity of calf hepatocytes by regulating the mTOR pathway activity.Thus,in addition to improving the glucose production potential,propionate may have therapeutic potential for the treatment of hepatic injury in dairy cows.
