-
Journal of Bone and Mineral Research :... Dec 2020Cellular bioenergetics is a promising new therapeutic target in aging, cancer, and diabetes because these pathologies are characterized by a shift from oxidative to...
Cellular bioenergetics is a promising new therapeutic target in aging, cancer, and diabetes because these pathologies are characterized by a shift from oxidative to glycolytic metabolism. We have previously reported such glycolytic shift in aged bone as a major contributor to bone loss in mice. We and others also showed the importance of oxidative phosphorylation (OxPhos) for osteoblast differentiation. It is therefore reasonable to propose that stimulation of OxPhos will have bone anabolic effect. One strategy widely used in cancer research to stimulate OxPhos is inhibition of glycolysis. In this work, we aimed to evaluate the safety and efficacy of pharmacological inhibition of glycolysis to stimulate OxPhos and promote osteoblast bone-forming function and bone anabolism. We tested a range of glycolytic inhibitors including 2-deoxyglucose, dichloroacetate, 3-bromopyruvate, and oxamate. Of all the studied inhibitors, only a lactate dehydrogenase (LDH) inhibitor, oxamate, did not show any toxicity in either undifferentiated osteoprogenitors or osteoinduced cells in vitro. Oxamate stimulated both OxPhos and osteoblast differentiation in osteoprogenitors. In vivo, oxamate improved bone mineral density, cortical bone architecture, and bone biomechanical strength in both young and aged C57BL/6J male mice. Oxamate also increased bone formation by osteoblasts without affecting bone resorption. In sum, our work provided a proof of concept for the use of anti-glycolytic strategies in bone and identified a small molecule LDH inhibitor, oxamate, as a safe and efficient bone anabolic agent. © 2020 American Society for Bone and Mineral Research (ASBMR).
Topics: Anabolic Agents; Animals; Glycolysis; L-Lactate Dehydrogenase; Male; Mice; Mice, Inbred C57BL; Oxidative Phosphorylation
PubMed: 32729639
DOI: 10.1002/jbmr.4142 -
Cancer Cell Sep 2016Metabolic adaptability is essential for tumor progression and includes cooperation between cancer cells with different metabolic phenotypes. Optimal glucose supply to...
Metabolic adaptability is essential for tumor progression and includes cooperation between cancer cells with different metabolic phenotypes. Optimal glucose supply to glycolytic cancer cells occurs when oxidative cancer cells use lactate preferentially to glucose. However, using lactate instead of glucose mimics glucose deprivation, and glucose starvation induces autophagy. We report that lactate sustains autophagy in cancer. In cancer cells preferentially to normal cells, lactate dehydrogenase B (LDHB), catalyzing the conversion of lactate and NAD(+) to pyruvate, NADH and H(+), controls lysosomal acidification, vesicle maturation, and intracellular proteolysis. LDHB activity is necessary for basal autophagy and cancer cell proliferation not only in oxidative cancer cells but also in glycolytic cancer cells.
Topics: Animals; Autophagy; Cell Line, Tumor; Cell Proliferation; Human Umbilical Vein Endothelial Cells; Humans; Isoenzymes; L-Lactate Dehydrogenase; Lysosomes; Mice; Neoplasms
PubMed: 27622334
DOI: 10.1016/j.ccell.2016.08.005 -
Cell Death & Disease Mar 2024Metabolic reprogramming, a hallmark of cancer, is closely associated with tumor development and progression. Changes in glycolysis play a crucial role in conferring...
Metabolic reprogramming, a hallmark of cancer, is closely associated with tumor development and progression. Changes in glycolysis play a crucial role in conferring radiation resistance to tumor cells. How radiation changes the glycolysis status of cancer cells is still unclear. Here we revealed the role of TAB182 in regulating glycolysis and lactate production in cellular response to ionizing radiation. Irradiation can significantly stimulate the production of TAB182 protein, and inhibiting TAB182 increases cellular radiosensitivity. Proteomic analysis indicated that TAB182 influences several vital biological processes, including multiple metabolic pathways. Knockdown of TAB182 results in decreased lactate production and increased pyruvate and ATP levels in cancer cells. Moreover, knocking down TAB182 reverses radiation-induced metabolic changes, such as radioresistant-related lactate production. TAB182 is necessary for activating LDHA transcription by affecting transcription factors SP1 and c-MYC; its knockdown attenuates the upregulation of LDHA by radiation, subsequently suppressing lactate production. Targeted suppression of TAB182 significantly enhances the sensitivity of murine xenograft tumors to radiotherapy. These findings advance our understanding of glycolytic metabolism regulation in response to ionizing radiation, which may offer significant implications for developing new strategies to overcome tumor radioresistance.
Topics: Humans; Animals; Mice; L-Lactate Dehydrogenase; Lactate Dehydrogenase 5; Proteomics; Cell Line, Tumor; Glycolysis; Lactates; Radiation Tolerance
PubMed: 38480704
DOI: 10.1038/s41419-024-06588-8 -
Disease Markers 2022: Periodontitis is one of the most common chronic bacterial infections in humans involving the tooth-supporting tissue. The present study aimed to evaluate and compare...
: Periodontitis is one of the most common chronic bacterial infections in humans involving the tooth-supporting tissue. The present study aimed to evaluate and compare salivary biomarkers, including lactate dehydrogenase (LDH) and hemoglobin A1c (HbA1c), between patients with severe chronic periodontitis and healthy individuals. : This study was performed on 29 patients with severe chronic periodontitis and 30 healthy individuals at Zahedan University of Medical Sciences, Zahedan, Iran, in 2021. Salivary samples were taken, and clinical parameters, including the clinical attachment loss (CAL) and probing pocket depth (PPD), were measured. Besides, the levels of LDH and HbA1c were measured using ELISA kits. The sensitivity, specificity, and positive and negative predictive values of HbA1c and LDH were examined for chronic periodontitis diagnosis. : Based on the present results, the levels of LDH and HbA1C did not show adequate sensitivity or specificity for screening chronic periodontitis. : According to the present findings, salivary biomarkers, including LDH and HbA1c, cannot be used with certainty for screening chronic periodontitis.
Topics: Biomarkers; Chronic Periodontitis; Glycated Hemoglobin; Humans; L-Lactate Dehydrogenase; Periodontal Index; Saliva
PubMed: 35521636
DOI: 10.1155/2022/1119038 -
Clinical Oral Investigations Jun 2021Detecting bacterial activity is considered a promising approach to monitor shifts from symbiosis to dysbiosis in oral microbiome. The present study aimed at...
OBJECTIVES
Detecting bacterial activity is considered a promising approach to monitor shifts from symbiosis to dysbiosis in oral microbiome. The present study aimed at investigating both the relative bacterial activity and the lactate dehydrogenase (ldh) gene expression of caries-associated bacteria in a site-specific natural biofilm.
MATERIAL AND METHODS
Sixty subjects (age, mean ± SE: 30.1 ± 1.4) were allocated to two groups: caries-free subjects (CF) or caries-active subjects (CA). CF presented one sound surface (CFS, n = 30). CA presented two donor sites: a cavitated caries lesion (CAC, n = 30) and a sound reference surface (CAS, n = 30). Real-time quantitative PCR (q-PCR) on species or genus level and total bacteria was performed targeting the 16S gene, the 16S rRNA, the ldh gene, and the ldh mRNA (increasing 16S ribosomal RNA copy numbers can function as an indicator of increased energy metabolism). As the 16S rRNA abundance represents the number of ribosomes, while the 16S gene abundance represents the number of genomes, the quotient of the relative abundances functions as a measure for the relative bacterial activity (%).
RESULTS
Both lactobacilli and S. mutans showed the highest relative bacterial activity in CAC ((mean ± SE) 218 ± 60% and 61 ± 16%, respectively) and the lowest values for both sound reference surfaces (69 ± 48%; 8 ± 3%). Significant differences were found between CAC and CAS as well as between CAC and CFS for both lactobacilli and S. mutans (p < 0.05). The ldh gene expression of lactobacilli and S. mutans only showed moderate values in CAC (1.90E+03 ± 2.11E+03; 2.08E+04 ± 4.44E+04 transcripts/μl) and CFS (2.04E+03 ± 2.74E+03; 8.16E+03 ± 6.64E+03 transcripts/μl); consequently no significant differences were detected.
CONCLUSION AND CLINICAL RELEVANCE
Caries-associated bacteria (lactobacilli and S. mutans) showed the highest relative bacterial activity in plaque of cavitated lesions, the lowest in sound surfaces, allowing the detection of a significant activity shift in health and disease for caries-active patients. However, no significant differences in ldh gene expression could be determined.
Topics: Bacteria; Biofilms; Dental Caries; Dental Caries Susceptibility; Gene Expression; Humans; L-Lactate Dehydrogenase; RNA, Ribosomal, 16S; Streptococcus mutans
PubMed: 33226500
DOI: 10.1007/s00784-020-03691-w -
ACS Applied Materials & Interfaces Feb 2022A novel double-resonant plasmonic substrate for fluorescence amplification in a chip-based apta-immunoassay is herein reported. The amplification mechanism relies on...
A novel double-resonant plasmonic substrate for fluorescence amplification in a chip-based apta-immunoassay is herein reported. The amplification mechanism relies on plasmon-enhanced fluorescence (PEF) effect. The substrate consists of an assembly of plasmon-coupled and plasmon-uncoupled gold nanoparticles (AuNPs) immobilized onto a glass slide. Plasmon-coupled AuNPs are hexagonally arranged along branch patterns whose resonance lies in the red band (∼675 nm). Plasmon-uncoupled AuNPs are sprinkled onto the substrate, and they exhibit a narrow resonance at 524 nm. Numerical simulations of the plasmonic response of the substrate through the finite-difference time-domain (FDTD) method reveal the presence of electromagnetic hot spots mainly confined in the interparticle junctions. In order to realize a PEF-based device for potential multiplexing applications, the plasmon resonances are coupled with the emission peak of 5-carboxyfluorescein (5-FAM) fluorophore and with the excitation/emission peaks of cyanine 5 (Cy5). The substrate is implemented in a malaria apta-immunoassay to detect lactate dehydrogenase (LDH) in human whole blood. Antibodies against biomarkers constitute the capture layer, whereas fluorescently labeled aptamers recognizing LDH are adopted as the top layer. The fluorescence emitted by 5-FAM and Cy5 fluorophores are linearly correlated (logarithm scale) to the LDH concentration over five decades. The limits of detection are 50 pM (1.6 ng/mL) with the 5-FAM probe and 260 fM (8.6 pg./mL) with the Cy5 probe. No sample preconcentration and complex pretreatments are required. Average fluorescence amplifications of 160 and 4500 are measured in the 5-FAM and Cy5 channel, respectively. These results are reasonably consistent with those worked out by FDTD simulations. The implementation of the proposed approach in multiwell-plate-based bioassays would lead to either signal redundancy (two dyes for a single analyte) or to a simultaneous detection of two analytes by different dyes, the latter being a key step toward high-throughput analysis.
Topics: Antibodies, Immobilized; Aptamers, Nucleotide; Carbocyanines; Fluoresceins; Glass; Gold; Humans; Immunoassay; L-Lactate Dehydrogenase; Limit of Detection; Metal Nanoparticles; Plasmodium falciparum; Protozoan Proteins; Surface Properties
PubMed: 35089707
DOI: 10.1021/acsami.1c23438 -
Chembiochem : a European Journal of... May 2022d-Phenyllactate (PLA) is a component of the selective Gq protein inhibitor and nonribosomal cyclic depsipeptide FR900359 (FR). Here we report a detailed biochemical...
d-Phenyllactate (PLA) is a component of the selective Gq protein inhibitor and nonribosomal cyclic depsipeptide FR900359 (FR). Here we report a detailed biochemical investigation of PLA biosynthesis and its incorporation into the natural product FR. The enzyme FrsC, member of the lactate/malate dehydrogenase superfamily, was shown to catalyze the formation of l-PLA from phenylpyruvate. FrsC was kinetically characterized and its substrate specificity determined. Incorporation of l-PLA was probed by assaying the adenylation domain FrsE-A3 and feeding studies with a Chromobacterium vaccinii ΔfrsC mutant, confirming preferred activation of l-PLA followed by on-line epimerization to d-PLA. Finally, detailed bioinformatic analyses of FrsC revealed its close relation to malate dehydrogenases from primary metabolism and suggest extensions in the substrate binding loop to be responsible for its adaptation to accepting larger aromatic substrates with high specificity.
Topics: Depsipeptides; L-Lactate Dehydrogenase; Lactates; Polyesters
PubMed: 34846772
DOI: 10.1002/cbic.202100569 -
Genes May 2021Lactate dehydrogenase (LDH) is a key enzyme in the last step of glycolysis, playing a role in the pyruvate-to-lactate reaction. It is associated with the prognosis and...
Lactate dehydrogenase (LDH) is a key enzyme in the last step of glycolysis, playing a role in the pyruvate-to-lactate reaction. It is associated with the prognosis and metastasis of many cancers, including breast cancer. In this study, we investigated the changes in gene expression and lactate concentrations in the culture media during tamoxifen resistance development in the MCF-7 cell line, and examined promoter methylation levels. An upregulation of 2.9 times of gene expression was observed around the IC50 concentration of tamoxifen in treated cells, while fluctuation in gene expression levels was found. Furthermore, morphological changes in the cell shape accompanied the changes in gene expression. Bisulfate treatment followed by sequencing of the promoter was performed to track any change in methylation levels; hypomethylation of CpG areas was found, suggesting that gene expression upregulation could be due to methylation level changes. Changes in and gene expression were correlated with the increase in lactate concentration in the culture media of treated MCF-7 cells.
Topics: Breast Neoplasms; Cell Line, Tumor; DNA Methylation; Drug Resistance, Neoplasm; Female; Gene Expression; Gene Expression Regulation, Neoplastic; Glycolysis; Humans; L-Lactate Dehydrogenase; Lactic Acid; MCF-7 Cells; Prognosis; Promoter Regions, Genetic; Tamoxifen; Up-Regulation
PubMed: 34069745
DOI: 10.3390/genes12050777 -
Molecules (Basel, Switzerland) Nov 2021Plasmodium lactate dehydrogenase (pLH) is one of the enzymes in glycolysis with potential target for chemotherapy. This study aimed to clone, overexpress and...
Plasmodium lactate dehydrogenase (pLH) is one of the enzymes in glycolysis with potential target for chemotherapy. This study aimed to clone, overexpress and characterize soluble recombinant lactate dehydrogenase from in a bacterial system. Synthetic lactate dehydrogenase (-LDH) gene was cloned into pET21a expression vector, transformed into strain BL21 (DE3) expression system and then incubated for 18 h, 20 °C with the presence of 0.5 mM isopropyl β-d-thiogalactoside in Terrific broth supplemented with Magnesium sulfate, followed by protein purifications using Immobilized Metal Ion Affinity Chromatography and size exclusion chromatography (SEC). Enzymatic assay was conducted to determine the activity of the enzyme. SDS-PAGE analysis revealed that protein of 34 kDa size was present in the soluble fraction. In SEC, a single peak corresponding to the size of -LDH protein was observed, indicating that the protein has been successfully purified. From MALDI-TOF analysis findings, a peptide score of 282 was established, which is significant for lactate dehydrogenase from revealed via MASCOT analysis. Secondary structure analysis of CD spectra indicated 79.4% α helix and 1.37% β strand structure. Specific activity of recombinant -LDH was found to be 475.6 U/mg, confirming the presence of active protein. Soluble -LDH that is biologically active was produced, which can be used further in other malaria studies.
Topics: Antimalarials; L-Lactate Dehydrogenase; Malaria; Plasmodium knowlesi
PubMed: 34771034
DOI: 10.3390/molecules26216625 -
Drug Design, Development and Therapy 2016Praziquantel (PZQ) is prescribed as a racemic mixture (racemic-PZQ, rac-PZQ), which is composed of (R)-PZQ and (S)-PZQ. In this work, the cytotoxicity of rac-PZQ and its...
Praziquantel (PZQ) is prescribed as a racemic mixture (racemic-PZQ, rac-PZQ), which is composed of (R)-PZQ and (S)-PZQ. In this work, the cytotoxicity of rac-PZQ and its two enantiomers (R)-PZQ and (S)-PZQ on eight cell lines (L-02, HepG2, prf-plc-5, SH-SY5Y, HUVEC, A549, HCT-15, Raw264.7) was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphe-nyltetrazolium bromide and lactate dehydrogenase assays. The morphology of apoptotic cells was studied by fluorescence microscope using Hoechst 33342 staining, and the cytotoxicity of the compounds was also tested by lactate dehydrogenase assay. Results revealed that (R)-PZQ had negligible cytotoxicity against L-02, SH-SY5Y, HUVEC, A549, HCT-15, and Raw264.7 cells but selectively inhibited tumor cell lines (prf-plc-5 and HepG2). However, in contrast to (R)-PZQ, the (S)-isomer showed higher cytotoxicity against L-02 cells and lower inhibition on prf-plc-5 and HepG2 cells. Besides, (R)-PZQ showed lower cytotoxicity on SH-SY5Y cells than (S)-PZQ. Meanwhile, (R)-PZQ at <80 μM concentration could promote proliferation of macrophage cells (Raw264.7). Our research revealed that (R)-PZQ has lower cytotoxicity than (S)-PZQ and has similar cytotoxicity with rac-PZQ. (S)-PZQ is the principal enantiomer to cause side effects on human definitive hosts. These findings gave the reasonable reasons for World Health Organization to produce (R)-PZQ as a replacement for rac-PZQ for the treatment of schistosomiasis.
Topics: Cell Line, Tumor; Hep G2 Cells; Humans; L-Lactate Dehydrogenase; Praziquantel; Schistosomiasis; Stereoisomerism; Tetrazolium Salts; Thiazoles
PubMed: 27445457
DOI: 10.2147/DDDT.S98096