Metabolic reprogramming, a newly recognized trait of tumor biology, is an intensively studied prospect for oncology medicines. For numerous tumors and cancer cell subpopulations, oxidative phosphorylation (OXPHOS) is essential for their biosynthetic and bioenergetic functions. Cancer cells with mutations in isocitrate dehydrogenase 1 (IDH1) exhibit differentiation arrest, epigenetic and transcriptional reprogramming, and sensitivity to mitochondrial OXPHOS inhibitors. In this study, we report that berberine, which is widely used in China to treat intestinal infections, acted solely at the mitochondrial electron transport chain (ETC) complex I, and that its association with IDH1 mutant inhibitor (IDH1^mi) AG-120 decreased mitochondrial activity and enhanced antileukemic effect in vitro andin vivo. Our study gives a scientific rationale for the therapy of IDH1 mutant acute myeloid leukemia (AML) patients using combinatory mitochondrial targeted medicines, particularly those who are resistant to or relapsing from IDH1^mi.
Humans ; Oxidative Phosphorylation ; Berberine ; Electron Transport ; Mitochondria ; Leukemia, Myeloid, Acute ; Isocitrate Dehydrogenase

OBJECTIVE: To investigate the potential mechanisms that mediate the inhibitory effect of porcine recombinant NKlysin (prNK-lysin) against liver cancer cell metastasis. METHODS: HPLC-tandem mass spectrometry was used to identify the differentially expressed proteins in prNK-lysin-treated hepatocellular carcinoma SMMOL/LC-7721 cells in comparison with the control and PBS-treated cells. GO functional annotation and KEGG pathway analysis of the differentially expressed proteins were performed using GO and KEGG databases. RT-qPCR was used to determine the mRNA expression levels of polypeptide-N-acetylgalactosaminotransferase 13 (GALNT13), transmembrane protein 51 (TMEM51) and FKBP prolyl isomerase 3 (FKBP3) in the cells, and the protein expression of FKBP3 was verified using Western blotting. RESULTS: Proteomic analysis identified 1989 differentially expressed proteins in prNK-lysin-treated cells compared with the control cells, and 2753 compared with PBS-treated cells. Fifteen proteins were differentially expressed between PBS-treated and the control cells, and 1909 were differentially expressed in prNK- lysin group compared with both PBS and control groups. These differentially expressed proteins were involved mainly in the viral process, translational initiation and RNA binding and were enriched mainly in ribosome, protein process in endoplasmic reticulum, and RNA transport pathways. RT-qPCR showed that compared with the control group, prNK-lysin treatment significantly increased the mRNA expressions of GALNT13 (P < 0.05) and TMEM51 (P < 0.01) and lowered FKBP3 mRNA expression (P < 0.05). Western blotting also showed a significantly decreased expression of FKBP3 protein in prNK-lysin-treated cells (P < 0.001). CONCLUSION Treatment with prNK-lysin causes significant changes in protein expression profile of SMMOL/LC-7721 cells and inhibits hepatocellular carcinoma metastasis by downregulating FKBP3 protein and affecting the cellular oxidative phosphorylation and glycolysis pathways.
Animals ; Swine ; Carcinoma, Hepatocellular/pathology* ; Liver Neoplasms/pathology* ; Oxidative Phosphorylation ; Proteomics ; Glycolysis ; RNA, Messenger

Oxidative Phosphorylation ; Acetylglucosamine ; Uridine Diphosphate N-Acetylglucosamine/metabolism*

The metabolic reprogramming of tumor cells is characterized by increased uptake of various nutrients including glutamine. Glutamine metabolism provides the required substances for glycolysis and oxidative phosphorylation and affects the homeostasis of carbohydrate，fat and protein metabolism to induce the chemoresistance of tumor cells. Combination of chemotherapeutic agents with inhibitors specific to different components of glutamine metabolic pathway has obtained favorable clinical results on various tumors. Glutamine metabolic pathway plays a role in drug resistance of tumor cells in various ways. Firstly，the dynamic change of glutamine transporters can directly affect intracellular glutamine content thereby causing drug resistance; secondly，tumor stromal cells including adipocyte，fibroblast and metabolite from tumor microenvironment would give rise to immune-mediated drug resistance; thirdly，the expression and activity of key enzymes in glutamine metabolism also has a critical role in drug resistance of tumors. This article reviews the effects of glutamine metabolic pathway in the development of tumor chemoresistance，in terms of transporters，tumor microenvironment and metabolic enzymes，to provide insight for improving the therapeutic efficacy for drug-resistant tumors.
Cell Line, Tumor ; Drug Resistance, Neoplasm ; Glutamine/metabolism* ; Glycolysis ; Humans ; Neoplasms/drug therapy* ; Oxidative Phosphorylation ; Tumor Microenvironment

PURPOSE: The roles of gut microbiota on the natural course of atopic dermatitis (AD) are not yet fully understood. We investigated whether the composition and function of gut microbiota and short-chain fatty acids (SCFAs) at 6 months of age could affect the natural course of AD up to 24 months in early childhood.METHODS: Fecal samples from 132 infants were analyzed using pyrosequencing, including 84 healthy controls, 22 transient AD and 26 persistent AD subjects from the Cohort for Childhood Origin of Asthma and Allergic Diseases (COCOA) birth cohort. The functional profile of the gut microbiome was analyzed by whole-metagenome sequencing. SCFAs were measured using gas chromatography-mass spectrometry.RESULTS: Low levels of Streptococcus and high amounts of Akkermansia were evident in transient AD cases, and low Clostridium, Akkermansia and high Streptococcus were found in children with persistent AD. The relative abundance of Streptococcus positively correlated with scoring of AD (SCORAD) score, whereas that of Clostridium negatively correlated with SCORAD score. The persistent AD group showed decreased gut microbial functional genes related to oxidative phosphorylation compared with healthy controls. Butyrate and valerate levels were lower in transient AD infants compared with healthy and persistent AD infants.CONCLUSIONS: Compositions, functions and metabolites of the early gut microbiome are related to natural courses of AD in infants.
Asthma ; Butyrates ; Child ; Clostridium ; Cohort Studies ; Dermatitis, Atopic ; Fatty Acids, Volatile ; Gas Chromatography-Mass Spectrometry ; Gastrointestinal Microbiome ; Humans ; Infant ; Metabolomics ; Metagenome ; Oxidative Phosphorylation ; Parturition ; Streptococcus

Oxidative stress causes cell damage and death, which contribute to the pathogenesis of neurodegenerative diseases. Urolithin A (UA), a gut microbial-derived metabolite of ellagitannins and ellagic acid, has high bioavailability and various health benefits such as antioxidant and anti-inflammatory effects. However, it is unknown whether it has protective effects against oxidative stress-induced cell death. We investigated whether UA ameliorates H₂O₂-induced neuronal cell death.MATERIALS/METHODS: We induced oxidative damage with 300 µM H₂O₂ after UA pretreatment at concentrations of 1.25, 2.5, and 5 µM in SK-N-MC cells. Cytotoxicity and cell viability were determined using the CCK-8 assay. The formation of reactive oxygen species (ROS) was measured using a 2,7-dichlorofluorescein diacetate assay. Hoechst 33342 staining was used to characterize morphological changes in apoptotic cells. The expressions of apoptosis proteins were measured using Western blotting.RESULTS: UA significantly increased cell viability and decreased intracellular ROS production in a dose-dependent manner in SK-N-MC cells. It also decreased the Bax/Bcl-2 ratio and the expressions of cytochrome c, cleaved caspase-9, cleaved caspase-3, and cleaved PARP. In addition, it suppressed the phosphorylation of the p38 mitogen-activated protein kinase (MAPK) pathway.CONCLUSIONS: UA attenuates oxidative stress-induced apoptosis via inhibiting the mitochondrial-related apoptosis pathway and modulating the p38 MAPK pathway, suggesting that it may be an effective neuroprotective agent.]]>
Apoptosis ; Biological Availability ; Blotting, Western ; Caspase 3 ; Caspase 9 ; Cell Death ; Cell Survival ; Cytochromes c ; Ellagic Acid ; Hydrolyzable Tannins ; Insurance Benefits ; Neurodegenerative Diseases ; Neurons ; Neuroprotective Agents ; Oxidative Stress ; p38 Mitogen-Activated Protein Kinases ; Phosphorylation ; Protein Kinases ; Reactive Oxygen Species ; Sincalide

The complement cascade is a central component of innate immunity which plays a critical role in brain inflammation. Complement C3a receptor (C3aR) is a key mediator of post-ischemic cerebral injury, and pharmacological antagonism of the C3a receptor is neuroprotective in stroke. Cerebral ischemia injures brain endothelial cells, causing blood brain barrier (BBB) disruption which further exacerbates ischemic neuronal injury. In this study, we used an in vitro model of ischemia (oxygen glucose deprivation; OGD) to investigate the protective effect of a C3aR antagonist (C3aRA, SB290157) on brain endothelial cells (bEnd.3). Following 24 hours of reperfusion, OGD-induced cell death was assessed by TUNEL and Caspase-3 staining. Western blot and immunocytochemistry were utilized to demonstrate that OGD upregulates inflammatory, oxidative stress and antioxidant markers (ICAM-1, Cox-2, Nox-2 and MnSOD) in endothelial cells and that C3aRA treatment significantly attenuate these markers. We also found that C3aRA administration restored the expression level of the tight junction protein occludin in endothelial cells following OGD. Interestingly, OGD/reperfusion injury increased the phosphorylation of ERK1/2 and C3aR inhibition significantly reduced the activation of ERK suggesting that endothelial C3aR may act via ERK signaling. Furthermore, exogenous C3a administration stimulates these same inflammatory mechanisms both with and without OGD, and C3aRA suppresses these C3a-mediated responses, supporting an antagonist role for C3aRA. Based on these results, we conclude that C3aRA administration attenuates inflammation, oxidative stress, ERK activation, and protects brain endothelial cells following experimental brain ischemia.
Blood-Brain Barrier ; Blotting, Western ; Brain Ischemia ; Brain ; Caspase 3 ; Cell Death ; Complement C3a ; Complement System Proteins ; Encephalitis ; Endothelial Cells ; Glucose ; Immunity, Innate ; Immunohistochemistry ; In Situ Nick-End Labeling ; In Vitro Techniques ; Inflammation ; Ischemia ; Neurons ; Occludin ; Oxidative Stress ; Phosphorylation ; Reperfusion ; Stroke ; Tight Junctions

BACKGROUND: Chronic exposure to elevated levels of free fatty acids contributes to pancreatic β-cell dysfunction. Although it is well known that metformin induces cellular energy depletion and a concomitant activation of AMP-activated protein kinase (AMPK) through inhibition of the respiratory chain, previous studies have shown inconsistent results with regard to the action of metformin on pancreatic β-cells. We therefore examined the effects of metformin on pancreatic β-cells under lipotoxic stress.METHODS: NIT-1 cells and mouse islets were exposed to palmitate and treated with 0.05 and 0.5 mM metformin. Cell viability, glucose-stimulated insulin secretion, cellular adenosine triphosphate, reactive oxygen species (ROS) levels and Rho kinase (ROCK) activities were measured. The phosphorylation of AMPK was evaluated by Western blot analysis and mRNA levels of endoplasmic reticulum (ER) stress markers and NADPH oxidase (NOX) were measured by real-time quantitative polymerase chain reaction analysis.RESULTS: We found that metformin has protective effects on palmitate-induced β-cell dysfunction. Metformin at a concentration of 0.05 mM inhibits NOX and suppresses the palmitate-induced elevation of ER stress markers and ROS levels in a AMPK-independent manner, whereas 0.5 mM metformin inhibits ROCK activity and activates AMPK.CONCLUSION: This study suggests that the action of metformin on β-cell lipotoxicity was implemented by different molecular pathways depending on its concentration. Metformin at a usual therapeutic dose is supposed to alleviate lipotoxic β-cell dysfunction through inhibition of oxidative stress and ER stress.
Adenosine Triphosphate ; AMP-Activated Protein Kinases ; Animals ; Blotting, Western ; Cell Survival ; Electron Transport ; Endoplasmic Reticulum ; Endoplasmic Reticulum Stress ; Fatty Acids, Nonesterified ; Insulin ; Insulin-Secreting Cells ; Metformin ; Mice ; NADPH Oxidase ; Oxidative Stress ; Phosphorylation ; Polymerase Chain Reaction ; Reactive Oxygen Species ; rho-Associated Kinases ; RNA, Messenger

During virus infection, T cells must be adapted to activation and lineage differentiation states via metabolic reprogramming. Whereas effector CD8⁺ T cells preferentially use glycolysis for their rapid proliferation, memory CD8⁺ T cells utilize oxidative phosphorylation for their homeostatic maintenance. Particularly, enhanced AMP-activated protein kinase (AMPK) activity promotes the memory T cell response through different pathways. However, the level of AMPK activation required for optimal memory T cell differentiation remains unclear. A new metformin derivative, IM156, formerly known as HL156A, has been reported to ameliorate various types of fibrosis and inhibit in vitro and in vivo tumors by inducing AMPK activation more potently than metformin. Here, we evaluated the in vivo effects of IM156 on antigen-specific CD8⁺ T cells during their effector and memory differentiation after acute lymphocytic choriomeningitis virus infection. Unexpectedly, our results showed that in vivo treatment of IM156 exacerbated the memory differentiation of virus-specific CD8⁺ T cells, resulting in an increase in short-lived effector cells but decrease in memory precursor effector cells. Thus, IM156 treatment impaired the function of virus-specific memory CD8⁺ T cells, indicating that excessive AMPK activation weakens memory T cell differentiation, thereby suppressing recall immune responses. This study suggests that metabolic reprogramming of antigen-specific CD8⁺ T cells by regulating the AMPK pathway should be carefully performed and managed to improve the efficacy of T cell vaccine.
AMP-Activated Protein Kinases ; Cell Differentiation ; Fibrosis ; Glycolysis ; Immunologic Memory ; In Vitro Techniques ; Lymphocytic choriomeningitis virus ; Lymphocytic Choriomeningitis ; Memory ; Metformin ; Oxidative Phosphorylation ; T-Lymphocytes

Obesity results in an inflammatory microenvironment in adipose tissue, leading to the deterioration of tissue protective mechanisms. Although recent studies suggested the importance of type 2 immunity in an anti-inflammatory microenvironment in adipose tissue, the regulatory effects of T helper 2 (Th2) cytokines on systemic metabolic regulation are not fully understood. Recently, we identified the roles of the Th2 cytokine (interleukin 4 [IL-4] and IL-13)-induced adipokine, growth differentiation factor 15 (GDF15), in adipose tissue in regulating systemic glucose metabolism via signal transducer and activator of transcription 6 (STAT6) activation. Moreover, we showed that mitochondrial oxidative phosphorylation is required to maintain these macrophage-regulating autocrine and paracrine signaling pathways via Th2 cytokine-induced secretion of GDF15. In this review, we discuss how the type 2 immune response and Th2 cytokines regulate metabolism in adipose tissue. Specifically, we review the systemic regulatory roles of Th2 cytokines in metabolic disease and the role of mitochondria in maintenance of type 2 responses in adipose tissue homeostasis.
Adipokines ; Adipose Tissue ; Cytokines ; Glucose ; Growth Differentiation Factor 15 ; Homeostasis ; Metabolic Diseases ; Metabolism ; Mitochondria ; Obesity ; Oxidative Phosphorylation ; Paracrine Communication ; STAT6 Transcription Factor