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Frontiers in Immunology 2023Excessive renal fibrosis is a common pathology in progressive chronic kidney diseases. Inflammatory injury and aberrant repair processes contribute to the development of...
Excessive renal fibrosis is a common pathology in progressive chronic kidney diseases. Inflammatory injury and aberrant repair processes contribute to the development of kidney fibrosis. Myeloid cells, particularly monocytes/macrophages, play a crucial role in kidney fibrosis by releasing their proinflammatory cytokines and extracellular matrix components such as collagen and fibronectin into the microenvironment of the injured kidney. Numerous signaling pathways have been identified in relation to these activities. However, the involvement of metabolic pathways in myeloid cell functions during the development of renal fibrosis remains understudied. In our study, we initially reanalyzed single-cell RNA sequencing data of renal myeloid cells from Dr. Denby's group and observed an increased gene expression in glycolytic pathway in myeloid cells that are critical for renal inflammation and fibrosis. To investigate the role of myeloid glycolysis in renal fibrosis, we utilized a model of unilateral ureteral obstruction in mice deficient of , an activator of glycolysis, in myeloid cells and their wild type littermates ( ). We observed a significant reduction in fibrosis in the obstructive kidneys of mice compared to mice. This was accompanied by a substantial decrease in macrophage infiltration, as well as a decrease of M1 and M2 macrophages and a suppression of macrophage to obtain myofibroblast phenotype in the obstructive kidneys of mice. Mechanistic studies indicate that glycolytic metabolites stabilize HIF1α, leading to alterations in macrophage phenotype that contribute to renal fibrosis. In conclusion, our study implicates that targeting myeloid glycolysis represents a novel approach to inhibit renal fibrosis.
Topics: Animals; Mice; Fibrosis; Glycolysis; Kidney; Kidney Diseases; Macrophages; Phosphofructokinase-2
PubMed: 38035106
DOI: 10.3389/fimmu.2023.1259434 -
Journal of Experimental & Clinical... Dec 2023Cancer cells undergo cellular adaptation through metabolic reprogramming to sustain survival and rapid growth under various stress conditions. However, how brain tumors...
BACKGROUND
Cancer cells undergo cellular adaptation through metabolic reprogramming to sustain survival and rapid growth under various stress conditions. However, how brain tumors modulate their metabolic flexibility in the naturally serine/glycine (S/G)-deficient brain microenvironment remain unknown.
METHODS
We used a range of primary/stem-like and established glioblastoma (GBM) cell models in vitro and in vivo. To identify the regulatory mechanisms of S/G deprivation-induced metabolic flexibility, we employed high-throughput RNA-sequencing, transcriptomic analysis, metabolic flux analysis, metabolites analysis, chromatin immunoprecipitation (ChIP), luciferase reporter, nuclear fractionation, cycloheximide-chase, and glucose consumption. The clinical significances were analyzed in the genomic database (GSE4290) and in human GBM specimens.
RESULTS
The high-throughput RNA-sequencing and transcriptomic analysis demonstrate that the de novo serine synthesis pathway (SSP) and glycolysis are highly activated in GBM cells under S/G deprivation conditions. Mechanistically, S/G deprivation rapidly induces reactive oxygen species (ROS)-mediated AMP-activated protein kinase (AMPK) activation and AMPK-dependent hypoxia-inducible factor (HIF)-1α stabilization and transactivation. Activated HIF-1α in turn promotes the expression of SSP enzymes phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH). In addition, the HIF-1α-induced expression of glycolytic genes (GLUT1, GLUT3, HK2, and PFKFB2) promotes glucose uptake, glycolysis, and glycolytic flux to fuel SSP, leading to elevated de novo serine and glycine biosynthesis, NADPH/NADP ratio, and the proliferation and survival of GBM cells. Analyses of human GBM specimens reveal that the levels of overexpressed PHGDH, PSAT1, and PSPH are positively correlated with levels of AMPK T172 phosphorylation and HIF-1α expression and the poor prognosis of GBM patients.
CONCLUSION
Our findings reveal that metabolic stress-enhanced glucose-derived de novo serine biosynthesis is a critical metabolic feature of GBM cells, and highlight the potential to target SSP for treating human GBM.
Topics: Humans; AMP-Activated Protein Kinases; Glioblastoma; Serine; Glucose; Glycine; RNA; Hypoxia-Inducible Factor 1, alpha Subunit; Cell Line, Tumor; Tumor Microenvironment; Phosphofructokinase-2
PubMed: 38098117
DOI: 10.1186/s13046-023-02927-3 -
Cell Reports Nov 2023Aerobic glycolysis is critical for cancer progression and can be exploited in cancer therapy. Here, we report that the human carboxymethylenebutenolidase homolog...
Aerobic glycolysis is critical for cancer progression and can be exploited in cancer therapy. Here, we report that the human carboxymethylenebutenolidase homolog (carboxymethylenebutenolidase-like [CMBL]) acts as a tumor suppressor by reprogramming glycolysis in colorectal cancer (CRC). The anti-cancer action of CMBL is mediated through its interactions with the E3 ubiquitin ligase TRIM25 and the glycolytic enzyme phosphofructokinase-1 platelet type (PFKP). Ectopic CMBL enhances TRIM25 binding to PFKP, leading to the ubiquitination and proteasomal degradation of PFKP. Interestingly, CMBL is transcriptionally activated by p53 in response to genotoxic stress, and p53 activation represses glycolysis by promoting PFKP degradation. Remarkably, CMBL deficiency, which impairs p53's ability to inhibit glycolysis, makes tumors more sensitive to a combination therapy involving the glycolysis inhibitor 2-deoxyglucose. Taken together, our study demonstrates that CMBL suppresses CRC growth by inhibiting glycolysis and suggests a potential combination strategy for the treatment of CMBL-deficient CRC.
Topics: Humans; Cell Line, Tumor; Glucose; Glycolysis; Neoplasms; Phosphofructokinase-1; Phosphofructokinase-1, Type C; Phosphofructokinases; Tumor Suppressor Protein p53
PubMed: 37967006
DOI: 10.1016/j.celrep.2023.113426 -
Cell Reports Oct 2023Metastasis is the leading cause of high ovarian-cancer-related mortality worldwide. Three major processes constitute the whole metastatic cascade: invasion,...
Metastasis is the leading cause of high ovarian-cancer-related mortality worldwide. Three major processes constitute the whole metastatic cascade: invasion, intravasation, and extravasation. Tumor cells often reprogram their metabolism to gain advantages in proliferation and survival. However, whether and how those metabolic alterations contribute to the invasiveness of tumor cells has yet to be fully understood. Here we performed a genome-wide CRISPR-Cas9 screening to identify genes participating in tumor cell dissemination and revealed that PTGES3 acts as an invasion suppressor in ovarian cancer. Mechanistically, PTGES3 binds to phosphofructokinase, liver type (PFKL) and generates a local source of prostaglandin E2 (PGE2) to allosterically inhibit the enzymatic activity of PFKL. Repressed PFKL leads to downgraded glycolysis and the subsequent TCA cycle for glucose metabolism. However, ovarian cancer suppresses the expression of PTGES3 and disrupts the PTGES3-PGE2-PFKL inhibitory axis, leading to hyperactivation of glucose oxidation, eventually facilitating ovarian cancer cell motility and invasiveness.
Topics: Humans; Female; Dinoprostone; Phosphofructokinases; Phosphofructokinase-1; Liver; Glucose; Ovarian Neoplasms; Cell Proliferation; Cell Line, Tumor; Neoplasm Invasiveness
PubMed: 37831605
DOI: 10.1016/j.celrep.2023.113246 -
Redox Biology Jul 2023Mitochondrial supercomplexes are observed in mammalian tissues with high energy demand and may influence metabolism and redox signaling. Nevertheless, the mechanisms...
Mitochondrial supercomplexes are observed in mammalian tissues with high energy demand and may influence metabolism and redox signaling. Nevertheless, the mechanisms that regulate supercomplex abundance remain unclear. In this study, we examined the composition of supercomplexes derived from murine cardiac mitochondria and determined how their abundance changes with substrate provision or by genetically induced changes to the cardiac glucose-fatty acid cycle. Protein complexes from digitonin-solubilized cardiac mitochondria were resolved by blue-native polyacrylamide gel electrophoresis and were identified by mass spectrometry and immunoblotting to contain constituents of Complexes I, III, IV, and V as well as accessory proteins involved in supercomplex assembly and stability, cristae architecture, carbohydrate and fat oxidation, and oxidant detoxification. Respiratory analysis of high molecular mass supercomplexes confirmed the presence of intact respirasomes, capable of transferring electrons from NADH to O. Provision of respiratory substrates to isolated mitochondria augmented supercomplex abundance, with fatty acyl substrate (octanoylcarnitine) promoting higher supercomplex abundance than carbohydrate-derived substrate (pyruvate). Mitochondria isolated from transgenic hearts that express kinase-deficient 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (Glyco), which decreases glucose utilization and increases reliance on fatty acid oxidation for energy, had higher mitochondrial supercomplex abundance and activity compared with mitochondria from wild-type or phosphatase-deficient 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-expressing hearts (Glyco), the latter of which encourages reliance on glucose catabolism for energy. These findings indicate that high energetic reliance on fatty acid catabolism bolsters levels of mitochondrial supercomplexes, supporting the idea that the energetic state of the heart is regulatory factor in supercomplex assembly or stability.
Topics: Mice; Animals; Phosphofructokinase-2; Heart; Mitochondria, Heart; Glucose; Fatty Acids; Mammals
PubMed: 37210780
DOI: 10.1016/j.redox.2023.102740 -
Science Advances Dec 2022Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by defective regulatory T (T) cells. Here, we demonstrate that a T cell-specific deletion of...
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by defective regulatory T (T) cells. Here, we demonstrate that a T cell-specific deletion of calcium/calmodulin-dependent protein kinase 4 (CaMK4) improves disease in B6. lupus-prone mice and expands T cells. Mechanistically, CaMK4 phosphorylates the glycolysis rate-limiting enzyme 6-phosphofructokinase, platelet type (PFKP) and promotes aerobic glycolysis, while its end product fructose-1,6-biphosphate suppresses oxidative metabolism. In T cells, a CRISPR-Cas9-enabled deletion recapitulated the metabolism of T cells and improved their function and stability in vitro and in vivo. In SLE CD4 T cells, PFKP enzymatic activity correlated with SLE disease activity and pharmacologic inhibition of CaMK4-normalized PFKP activity, leading to enhanced T cell function. In conclusion, we provide molecular insights in the defective metabolism and function of T cells in SLE and identify PFKP as a target to fine-tune T cell metabolism and thereby restore their function.
Topics: Animals; Mice; Phosphofructokinases; Autoimmunity; T-Lymphocytes, Regulatory; Immunotherapy; Lupus Erythematosus, Systemic
PubMed: 36449620
DOI: 10.1126/sciadv.adc9657 -
Aging May 2023The 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFK-2/FBPase-2, PFKFB3) is a glycolysis regulatory enzyme and plays a key role in oncogenesis of several...
The 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFK-2/FBPase-2, PFKFB3) is a glycolysis regulatory enzyme and plays a key role in oncogenesis of several cancers. However, the systematic study of crosstalk between PFKFB3 and Tumor microenvironment (TME) in pan-cancer has less been examined. In this study, we conducted a comprehensive analysis of the relationship between expression, patient prognostic, Tumor mutational burden (TMB), Microsatellite instability (MSI), DNA mismatch repair (MMR), and especially TME, including immune infiltration, immune regulator, and immune checkpoint, across 33 types of tumors using datasets of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). We found that expression was significantly correlated with patient prognostic and TME factors in various tumors. Moreover, we confirmed that PFKFB3 was an independent prognostic factor for kidney renal papillary cell carcinoma (KIRP), and established a risk prognostic model based on the expression of as a clinical risk factor, which has a good predictive ability. Our study indicated that PFKFB3 is a potent regulatory factor for TME and has the potential to be a valuable prognostic biomarker in human tumor therapy.
Topics: Humans; Biomarkers, Tumor; Glycolysis; Neoplasms; Phosphofructokinase-2; Prognosis; Tumor Microenvironment
PubMed: 37253634
DOI: 10.18632/aging.204758 -
Acta Pharmacologica Sinica Feb 2022Endothelial cells play an obligatory role in regulating local vascular tone and maintaining homeostasis in vascular biology. Cell metabolism, converting food to energy... (Review)
Review
Endothelial cells play an obligatory role in regulating local vascular tone and maintaining homeostasis in vascular biology. Cell metabolism, converting food to energy in organisms, is the primary self-sustaining mechanism for cell proliferation and reproduction, structure maintenance, and fight-or-flight responses to stimuli. Four major metabolic processes take place in the energy-producing process, including glycolysis, oxidative phosphorylation, glutamine metabolism, and fatty acid oxidation. Among them, glycolysis is the primary energy-producing mechanism in endothelial cells. The present review focused on glycolysis in endothelial cells under both physiological and pathological conditions. Since the switches among metabolic processes precede the functional changes and disease developments, some prophylactic and/or therapeutic strategies concerning the role of glycolysis in cardiovascular disease are discussed.
Topics: Animals; Cell Communication; Endothelial Cells; Glycolysis; Humans; Metabolic Networks and Pathways; Signal Transduction
PubMed: 33850277
DOI: 10.1038/s41401-021-00647-y -
British Journal of Pharmacology Nov 2022Macrophage-rich atherosclerotic arteries are highly active in glycolysis. PFKFB3, a key glycolytic enzyme, has emerged as a potential therapeutic target in...
BACKGROUND AND PURPOSE
Macrophage-rich atherosclerotic arteries are highly active in glycolysis. PFKFB3, a key glycolytic enzyme, has emerged as a potential therapeutic target in atherosclerosis. Small-molecule inhibitors of PFKFB3, such as 3PO and PFK158, have demonstrated efficacy in hampering atherogenesis in preclinical models. However, genetic studies elucidating the role of Pfkfb3 in atherogenesis need to be conducted to validate pharmacological findings and to unveil potential pharmacological side effects.
EXPERIMENTAL APPROACH
Apoe mice with global heterozygous or myeloid cell-specific Pfkfb3 deficiency were fed a Western diet (WD), after which atherosclerosis development was determined. Monocyte subsets in atherosclerotic mice and patients were examined by flow cytometry. Monocyte infiltration was assayed by a Ly6C monocyte-specific latex labelling procedure. In situ efferocytosis was assessed on mouse aortic root sections. Additionally, metabolic status, macrophage motility, efferocytosis, and involved mechanisms were analysed in peritoneal macrophages.
KEY RESULTS
Global heterozygous or myeloid cell-specific Pfkfb3 deficiency reduced atherogenesis in Apoe mice. Mechanistic studies showed that PFKFB3 controlled the proliferation and infiltration of proinflammatory monocytes. Moreover, PFKFB3 expression was associated with inflammatory monocyte expansion in patients with atherosclerotic coronary artery disease. Surprisingly, homozygous loss of Pfkfb3 impaired macrophage efferocytosis and exacerbated atherosclerosis in Apoe mice. Mechanistically, PFKFB3-driven glycolysis was shown to be essential for actin polymerization, thus aiding the efferocytotic function of macrophages.
CONCLUSION AND IMPLICATIONS
Collectively, these findings suggest the existence of a double-edged sword effect of myeloid PFKFB3 on the pathogenesis of atherosclerosis and highlight the need for caution in developing anti-atherosclerotic strategies that target PFKFB3.
Topics: Actins; Animals; Apolipoproteins E; Atherosclerosis; Biology; Macrophages; Mice; Mice, Inbred C57BL; Mice, Knockout; Monocytes; Phosphofructokinase-2; Pyridines; Quinolines
PubMed: 35834356
DOI: 10.1111/bph.15926