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Cellular and Molecular Biology... Jun 2024Macrophages in the tumor microenvironment can polarize into M1 or M2 forms, with M2 macrophages (M2φ) promoting tumor growth and metastasis in cervical squamous cell...
Macrophages in the tumor microenvironment can polarize into M1 or M2 forms, with M2 macrophages (M2φ) promoting tumor growth and metastasis in cervical squamous cell carcinoma (CESC). This study explored the effects of M2φ on CESC metabolic reprogramming both in vitro and in vivo. Results showed that M2φ secreted CXCL1, which significantly increased CESC migration and metabolic regulation. Further experiments revealed that CXCL1 upregulated KDM6B to enhance PFKFB2 transcriptional activity, thus regulating CESC glucose metabolism. Transcriptome sequencing screened 5 upregulated genes related to glycolysis, with PFKFB2 showing the most significant increase in cells treated with rCXCL1. Dual-luciferase reporter assay confirmed that rCXCL1 enhances PFKFB2 transcriptional activity. Bioinformatics analysis revealed a high correlation between expressions of KDM6B and PFKFB2 in CESC. Mechanistic experiments demonstrated that KDM6B inhibited H3K27me3 modification to activate PFKFB2 transcriptional expression. In conclusion, M2φ secreted CXCL1 to promote CESC cell migration and invasion, and CXCL1 activated KDM6B expression in CESC cells, inhibiting H3K27 protein methylation modification, and enhanced PFKFB2 transcriptional activity to regulate CESC glucose metabolism. These results provided new insights into the complex interplay between the immune system and cancer metabolism, which may have broader implications for understanding and treating other types of cancer.
Topics: Chemokine CXCL1; Uterine Cervical Neoplasms; Humans; Female; Carcinoma, Squamous Cell; Macrophages; Phosphofructokinase-2; Cell Movement; Jumonji Domain-Containing Histone Demethylases; Animals; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; Mice; Tumor Microenvironment; Glucose; Mice, Nude; Glycolysis; Metabolic Reprogramming
PubMed: 38836678
DOI: 10.14715/cmb/2024.70.6.13 -
Turkish Journal of Medical Sciences 2023Type 1 diabetes mellitus (T1DM) is caused by the autoimmune-mediated destruction of insulin-producing cells (IPCs) and still has no effective cure. Better understanding...
BACKGROUND/AIM
Type 1 diabetes mellitus (T1DM) is caused by the autoimmune-mediated destruction of insulin-producing cells (IPCs) and still has no effective cure. Better understanding of the molecular mechanisms involved in the differentiation of embryonic stem cells (ESCs) into IPCs may help us improve the therapeutic strategies for treating T1DM. 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (Pfkfb1-4) are key regulators of glucose metabolism. Although Pfkfb3 has been shown to be required for the growth of early differentiated mouse ESCs (mESCs), more studies are needed to further assess the roles of Pfkfb isoenzymes in embryonic development and differentiation, particularly into specific cell types. In this study, we aimed to elucidate the changes in the expression of Pfkfb isoenzymes on the differentiation of mESCs into IPCs.
MATERIALS AND METHODS
A 3-step protocol was used to differentiate R1 and J1 mESCs into IPCs. The changes in the gene expression of MafA, MafB, Ins2, and Nkx6.1 (IPC specific markers) and Pfkfb1-4 were analyzed using real-time quantitative polymerase chain reaction (qPCR). Insulin expression and secretion were determined by immunofluorescence (IF) staining and the enzyme linked immunosorbent assay (ELISA), respectively.
RESULTS
Upon differentiation, the IPC specific markers in differentiated cells were upregulated. Continued differentiation was confirmed by the development of insulin-positive islet-like clusters that secreted insulin in response to glucose uptake. Expressions of the Pfkfb2 and Pfkfb3 isoenzymes were markedly increased in various stages of differentiation.
CONCLUSION
These findings suggest that Pfkfb2 and Pfkfb3 may impact the differentiation of mESCs into IPCs and the regulation of the insulin response to glucose levels. This study also lays a foundation for researchers to further probe the roles of Pfkfb isoenzymes on the differentiation of mESCs into IPCs and may open new avenues for regenerative medicine.
Topics: Animals; Mice; Cell Differentiation; Insulin; Insulin-Secreting Cells; Isoenzymes; Mouse Embryonic Stem Cells; Phosphofructokinase-2
PubMed: 38813509
DOI: 10.55730/1300-0144.5725 -
Peptides Aug 2024Glucagon-like peptide-1 signalling impacts glucose homeostasis and appetite thereby indirectly affecting substrate availability at the whole-body level. The incretin... (Review)
Review
Glucagon-like peptide-1 signalling impacts glucose homeostasis and appetite thereby indirectly affecting substrate availability at the whole-body level. The incretin canonically produces an insulinotropic effect, thereby lowering blood glucose levels by promoting the uptake and inhibiting the production of the sugar by peripheral tissues. Likewise, GLP-1 signalling within the central nervous system reduces the appetite and food intake, whereas its gastric effect delays the absorption of nutrients, thus improving glycaemic control and reducing the risk of postprandial hyperglycaemia. We review the molecular aspects of the GLP-1 signalling, focusing on its impact on intracellular energy metabolism. Whilst the incretin exerts its effects predominantly via a G receptor, which decodes the incretin signal into the elevation of intracellular cAMP levels, the downstream signalling cascades within the cell, acting on fast and slow timescales, resulting in an enhancement or an attenuation of glucose catabolism, respectively.
Topics: Glucagon-Like Peptide 1; Humans; Energy Metabolism; Signal Transduction; Insulin-Secreting Cells; Animals; Incretins; Glucose
PubMed: 38788902
DOI: 10.1016/j.peptides.2024.171243 -
Cellular and Molecular Life Sciences :... May 2024Diabetic cardiomyopathy (DCM) is a prevalent complication of type 2 diabetes (T2D). 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) is a glycolysis...
Diabetic cardiomyopathy (DCM) is a prevalent complication of type 2 diabetes (T2D). 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) is a glycolysis regulator. However, the potential effects of PFKFB3 in the DCM remain unclear. In comparison to db/m mice, PFKFB3 levels decreased in the hearts of db/db mice. Cardiac-specific PFKFB3 overexpression inhibited myocardial oxidative stress and cardiomyocyte apoptosis, suppressed mitochondrial fragmentation, and partly restored mitochondrial function in db/db mice. Moreover, PFKFB3 overexpression stimulated glycolysis. Interestingly, based on the inhibition of glycolysis, PFKFB3 overexpression still suppressed oxidative stress and apoptosis of cardiomyocytes in vitro, which indicated that PFKFB3 overexpression could alleviate DCM independent of glycolysis. Using mass spectrometry combined with co-immunoprecipitation, we identified optic atrophy 1 (OPA1) interacting with PFKFB3. In db/db mice, the knockdown of OPA1 receded the effects of PFKFB3 overexpression in alleviating cardiac remodeling and dysfunction. Mechanistically, PFKFB3 stabilized OPA1 expression by promoting E3 ligase NEDD4L-mediated atypical K6-linked polyubiquitination and thus prevented the degradation of OPA1 by the proteasomal pathway. Our study indicates that PFKFB3/OPA1 could be potential therapeutic targets for DCM.
Topics: Phosphofructokinase-2; Animals; Diabetic Cardiomyopathies; Ubiquitination; Mice; GTP Phosphohydrolases; Myocytes, Cardiac; Male; Oxidative Stress; Apoptosis; Myocardium; Mice, Inbred C57BL; Diabetes Mellitus, Type 2; Glycolysis; Humans; Protein Stability
PubMed: 38777955
DOI: 10.1007/s00018-024-05257-5 -
Biochimica Et Biophysica Acta.... Aug 2024Recent studies in Diffuse Midline Gliomas (DMG) demonstrated a strong connection between epigenome dysregulation and metabolic rewiring. Here, we evaluated the value of...
Recent studies in Diffuse Midline Gliomas (DMG) demonstrated a strong connection between epigenome dysregulation and metabolic rewiring. Here, we evaluated the value of targeting a glycolytic protein named Phosphofructo-2-kinase/Fructose-2,6-bisphosphatase 3 (PFKFB3) in H3.3K27M DMG. We observed that the viability of H3.3K27M cells is dramatically reduced by PFK15, a potent inhibitor of PFKFB3. Furthermore, PFKFB3 inhibition induced apoptosis and G2/M arrest. Interestingly, CRISPR-Knockout of the K27M mutant allele has a synergistic effect on the observed phenotype. Altogether, we identified PFKFB3 as a new target for H3.3K27M DMG, making PFK15 a potential candidate for future animal studies and clinical trials.
Topics: Humans; Glioma; Phosphofructokinase-2; Histones; Cell Line, Tumor; Child; Brain Neoplasms; Apoptosis; Mutation; Glycolysis
PubMed: 38777100
DOI: 10.1016/j.bbadis.2024.167248 -
Nature Metabolism Jun 2024Lipid droplet tethering with mitochondria for fatty acid oxidation is critical for tumor cells to counteract energy stress. However, the underlying mechanism remains...
Lipid droplet tethering with mitochondria for fatty acid oxidation is critical for tumor cells to counteract energy stress. However, the underlying mechanism remains unclear. Here, we demonstrate that glucose deprivation induces phosphorylation of the glycolytic enzyme phosphofructokinase, liver type (PFKL), reducing its activity and favoring its interaction with perilipin 2 (PLIN2). On lipid droplets, PFKL acts as a protein kinase and phosphorylates PLIN2 to promote the binding of PLIN2 to carnitine palmitoyltransferase 1A (CPT1A). This results in the tethering of lipid droplets and mitochondria and the recruitment of adipose triglyceride lipase to the lipid droplet-mitochondria tethering regions to engage lipid mobilization. Interfering with this cascade inhibits tumor cell proliferation, promotes apoptosis and blunts liver tumor growth in male mice. These results reveal that energy stress confers a moonlight function to PFKL as a protein kinase to tether lipid droplets with mitochondria and highlight the crucial role of PFKL in the integrated regulation of glycolysis, lipid metabolism and mitochondrial oxidation.
Topics: Lipid Droplets; Animals; Cell Proliferation; Mitochondria; Oxidation-Reduction; Mice; Humans; Glycolysis; Lipolysis; Male; Lipid Metabolism; Perilipin-2; Phosphorylation; Carnitine O-Palmitoyltransferase; Cell Line, Tumor
PubMed: 38773347
DOI: 10.1038/s42255-024-01047-2 -
BMC Complementary Medicine and Therapies May 2024Bawei Chenxiang Wan (BCW) is among the most effective and widely used therapies for coronary heart disease and angina pectoris in Tibet. However, whether it confers...
Bawei Chenxiang Wan ameliorates right ventricular hypertrophy in rats with high altitude heart disease by SIRT3-HIF1α-PDK/PDH signaling pathway improving fatty acid and glucose metabolism.
BACKGROUND
Bawei Chenxiang Wan (BCW) is among the most effective and widely used therapies for coronary heart disease and angina pectoris in Tibet. However, whether it confers protection through a right-ventricle (RV) myocardial metabolic mechanism is unknown.
METHODS
Male Sprague-Dawley rats were orally administrated with BCW, which was injected concurrently with a bolus of Sugen5416, and subjected to hypoxia exposure (SuHx; 5000 m altitude) for 4 weeks. Right ventricular hypertrophy (RVH) in high-altitude heart disease (HAHD) was assessed using Fulton's index (FI; ratio of RV to left ventricle + septum weights) and heart-weight-to-body-weight ratio (HW/BW). The effect of therapeutic administration of BCW on the RVH hemodynamics was assessed through catheterization (mean right ventricular pressure and mean pulmonary artery pressure (mRVP and mPAP, respectively)). Tissue samples were used to perform histological staining, and confirmatory analyses of mRNA and protein levels were conducted to detect alterations in the mechanisms of RVH in HAHD. The protective mechanism of BCW was further verified via cell culture.
RESULTS
BCW considerably reduced SuHx-associated RVH, as indicated by macro morphology, HW/BW ratio, FI, mPAP, mRVP, hypertrophy markers, heart function, pathological structure, and myocardial enzymes. Moreover, BCW can alleviate the disorder of glucose and fatty acid metabolism through upregulation of carnitine palmitoyltransferase1ɑ, citrate synthase, and acetyl-CoA and downregulation of glucose transport-4, phosphofructokinase, and pyruvate, which resulted in the reduced levels of free fatty acid and lactic acid and increased aerobic oxidation. This process may be mediated via the regulation of sirtuin 3 (SIRT3)-hypoxia-inducible factor 1α (HIF1α)-pyruvate dehydrogenase kinase (PDK)/pyruvate dehydrogenase (PDH) signaling pathway. Subsequently, the inhibition of SIRT3 expression by 3-TYP (a selective inhibitor of SIRT3) can reverse substantially the anti-RVH effect of BCW in HAHD, as indicated by hypertrophy marker and serum myocardial enzyme levels.
CONCLUSIONS
BCW prevented SuHx-induced RVH in HAHD via the SIRT3-HIF1ɑ-PDK/PDH signaling pathway to alleviate the disturbance in fatty acid and glucose metabolism. Therefore, BCW can be used as an alternative drug for the treatment of RVH in HAHD.
Topics: Animals; Rats, Sprague-Dawley; Male; Rats; Drugs, Chinese Herbal; Hypoxia-Inducible Factor 1, alpha Subunit; Hypertrophy, Right Ventricular; Sirtuin 3; Fatty Acids; Signal Transduction; Glucose; Altitude Sickness; Disease Models, Animal; Pyruvate Dehydrogenase Acetyl-Transferring Kinase
PubMed: 38750550
DOI: 10.1186/s12906-024-04490-6 -
Archives of Insect Biochemistry and... May 2024Studies on antiaging remedies in insect models sometimes show discrepancies in results. These discrepancies could be explained by different responses of short- and...
Studies on antiaging remedies in insect models sometimes show discrepancies in results. These discrepancies could be explained by different responses of short- and long-lived strains on the antiaging remedies. The purpose of the study was to test whether life-prolonging effects of alpha-ketoglutarate (AKG), observed in nematodes and fruit flies, would be reproduced in long-lived Drosophila melanogaster flies. Lifespan was assayed in flies kept in demographic cages. Fecundity, proportion of flies capable of negative geotaxis, starvation resistance, time of heat coma onset, levels of triacyglycerols, body glucose, glycogen, activities of glutamate dehydrogenase, catalase, glutathione-S-transferase, hexokinase, phosphofructokinase, pyruvate kinase, lactate, and glutamate dehydrogenases were assessed. Dietary AKG did not affect fly lifespan on the diet with 5% yeast and 5% sucrose (5Y:5S) and on the diet with 9% yeast and 1% sucrose (9Y:1S), but increased lifespan on the low-protein diet (1Y:9S). Twenty-five-day-old female flies fed a 5Y:5S diet with 10 mM AKG for 3 weeks, did not differ from the control group (without AKG) in climbing activity, resistance to heat stress, and starvation. The levels of glucose and glycogen were unaffected but the levels of triacylglycerols were lower in AKG-fed female flies. No differences in activities of glycolytic enzymes, NADPH-producing enzymes, glutamate dehydrogenase, oxygen consumption, and levels of oxidative stress markers were observed between the control and AKG-fed flies. However, AKG-fed flies had lower activities of catalase and glutathione-S-transferase. These results suggest that potential antiaging remedies, such as AKG, may not extend lifespan in long-living organisms despite influencing several metabolic parameters.
Topics: Animals; Drosophila melanogaster; Longevity; Ketoglutaric Acids; Female; Male; Dietary Supplements
PubMed: 38739777
DOI: 10.1002/arch.22116 -
Plants (Basel, Switzerland) Apr 2024Soil alkalization is an important environmental factor limiting crop production. Despite the importance of root secretion in the response of plants to alkali stress, the...
Soil alkalization is an important environmental factor limiting crop production. Despite the importance of root secretion in the response of plants to alkali stress, the regulatory mechanism is unclear. In this study, we applied a widely targeted metabolomics approach using a local MS/MS data library constructed with authentic standards to identify and quantify root exudates of wheat under salt and alkali stresses. The regulatory mechanism of root secretion in alkali-stressed wheat plants was analyzed by determining transcriptional and metabolic responses. Our primary focus was alkali stress-induced secreted metabolites (AISMs) that showed a higher secretion rate in alkali-stressed plants than in control and salt-stressed plants. This secretion was mainly induced by high-pH stress. We discovered 55 AISMs containing -COOH groups, including 23 fatty acids, 4 amino acids, 1 amino acid derivative, 7 dipeptides, 5 organic acids, 9 phenolic acids, and 6 others. In the roots, we also discovered 29 metabolites with higher levels under alkali stress than under control and salt stress conditions, including 2 fatty acids, 3 amino acid derivatives, 1 dipeptide, 2 organic acids, and 11 phenolic acids. These alkali stress-induced accumulated carboxylic acids may support continuous root secretion during the response of wheat plants to alkali stress. In the roots, RNAseq analysis indicated that 5 6-phosphofructokinase (glycolysis rate-limiting enzyme) genes, 16 key fatty acid synthesis genes, and 122 phenolic acid synthesis genes have higher expression levels under alkali stress than under control and salt stress conditions. We propose that the secretion of multiple types of metabolites with a -COOH group is an important pH regulation strategy for alkali-stressed wheat plants. Enhanced glycolysis, fatty acid synthesis, and phenolic acid synthesis will provide more energy and substrates for root secretion during the response of wheat to alkali stress.
PubMed: 38732442
DOI: 10.3390/plants13091227 -
Microbial Cell Factories May 2024Mycosporine-like amino acids (MAAs) are a class of strongly UV-absorbing compounds produced by cyanobacteria, algae and corals and are promising candidates for natural...
Reversing the directionality of reactions between non-oxidative pentose phosphate pathway and glycolytic pathway boosts mycosporine-like amino acid production in Saccharomyces cerevisiae.
BACKGROUND
Mycosporine-like amino acids (MAAs) are a class of strongly UV-absorbing compounds produced by cyanobacteria, algae and corals and are promising candidates for natural sunscreen components. Low MAA yields from natural sources, coupled with difficulties in culturing its native producers, have catalyzed synthetic biology-guided approaches to produce MAAs in tractable microbial hosts like Escherichia coli, Saccharomyces cerevisiae and Corynebacterium glutamicum. However, the MAA titres obtained in these hosts are still low, necessitating a thorough understanding of cellular factors regulating MAA production.
RESULTS
To delineate factors that regulate MAA production, we constructed a shinorine (mycosporine-glycine-serine) producing yeast strain by expressing the four MAA biosynthetic enzymes from Nostoc punctiforme in Saccharomyces cerevisiae. We show that shinorine is produced from the pentose phosphate pathway intermediate sedoheptulose 7-phosphate (S7P), and not from the shikimate pathway intermediate 3-dehydroquinate (3DHQ) as previously suggested. Deletions of transaldolase (TAL1) and phosphofructokinase (PFK1/PFK2) genes boosted S7P/shinorine production via independent mechanisms. Unexpectedly, the enhanced S7P/shinorine production in the PFK mutants was not entirely due to increased flux towards the pentose phosphate pathway. We provide multiple lines of evidence in support of a reversed pathway between glycolysis and the non-oxidative pentose phosphate pathway (NOPPP) that boosts S7P/shinorine production in the phosphofructokinase mutant cells.
CONCLUSION
Reversing the direction of flux between glycolysis and the NOPPP offers a novel metabolic engineering strategy in Saccharomyces cerevisiae.
Topics: Pentose Phosphate Pathway; Saccharomyces cerevisiae; Glycolysis; Amino Acids; Metabolic Engineering; Nostoc; Sugar Phosphates; Glycine; Cyclohexylamines
PubMed: 38725068
DOI: 10.1186/s12934-024-02365-6