scholarly journals Alteration of Mevalonate Pathway in Rat Splenic Lymphocytes: Possible Role in Cytokines Secretion Regulated by L-Theanine

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Chengjian Li ◽  
Qiongxian Yan ◽  
Shaoxun Tang ◽  
Wenjun Xiao ◽  
Zhiliang Tan
Keyword(s):  
Biosynthetic Pathway ◽  
Mevalonate Pathway ◽  
Drug Candidate ◽  
Splenic Lymphocytes ◽  
Immunomodulatory Effects ◽  
Nonprotein Amino Acid ◽  
Mrna And Protein Expression ◽  
Coa Reductase ◽  
Lymphocytes Subsets ◽  
Cytokines Secretion

L-Theanine is a nonprotein amino acid in tea, and its immunomodulatory function has been confirmed. This study aimed to investigate the effect of L-theanine addition on cytokines secretion in rat splenic lymphocytes and explore its potential immunomodulatory effects on the mevalonate biosynthetic pathway. Our results showed that L-theanine treatment did not influence the proliferation and division indexes of the splenic lymphocytes subsets. Interestingly, L-theanine treatment had regulated the contents of IFN-γ, IL-2, IL-4, IL-10, IL-12, and TNF-α  (P<0.001) except IL-6 and upregulated the mRNA and protein expression of Ras-related protein Rap-1A (Rap1A), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), and farnesyl diphosphate synthase (FDPs) (P<0.001). Additionally, there was a positive correlation between Rap1A and HMGCR proteins expression and IFN-γ, IL-4, and IL-6 levels. In conclusion, L-theanine regulated the secretion of cytokines probably by activating expression of Rap1A and HMGCR proteins involved in the mevalonate biosynthetic pathway in rat splenic lymphocytes. Therefore, L-theanine might be a promising potential drug candidate as immunopotentiator.

scholarly journals A QM/MM Evaluation of the Missing Step in the Reduction Mechanism of HMG-CoA by Human HMG-CoA Reductase

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1085
Author(s):  
Paula Mihaljević-Jurič ◽  
Sérgio F. Sousa
Keyword(s):  
Mevalonate Pathway ◽  
Atomic Level ◽  
Amino Acid Residues ◽  
Protonation State ◽  
Primary Target ◽  
Cholesterol Levels ◽  
The Subject ◽  
Electron Reduction ◽  
Dynamics Simulations ◽  
Coa Reductase

Statins are important drugs in the regulation of cholesterol levels in the human body that have as a primary target the enzyme β-hydroxy-β-methylglutaryl-CoA reductase (HMGR). This enzyme plays a crucial role in the mevalonate pathway, catalyzing the four-electron reduction of HMG-CoA to mevalonate. A second reduction step of this reaction mechanism has been the subject of much speculation in the literature, with different conflicting theories persisting to the present day. In this study, the different mechanistic hypotheses were evaluated with atomic-level detail through a combination of molecular dynamics simulations (MD) and quantum mechanics/molecular mechanics (QM/MM) calculations. The obtained Gibbs free activation and Gibbs free reaction energy (15 kcal mol−1 and −40 kcal mol−1) show that this hydride step takes place with the involvement of a cationic His405 and Lys639, and a neutral Glu98, while Asp715 remains in an anionic state. The results provide an atomic-level portrait of this step, clearly demonstrating the nature and protonation state of the amino acid residues involved, the energetics associated, and the structure and charge of the key participating atoms in the several intermediate states, finally elucidating this missing step.

scholarly journals Molecular Characterization of a Poly-β-Hydroxybutyrate-Producing Microbacterium Isolate

2015 ◽  
Vol 3 (2) ◽  
pp. 143-150 ◽  
Author(s):  
Yehia A. Osman ◽  
Ahmed Abd Elrazak ◽  
Wesam Khater ◽  
EL-Shahat Nashy ◽  
Attia Mohamadeen
Keyword(s):  
Biosynthetic Pathway ◽  
Nitrogen Deficiency ◽  
Rrna Gene ◽  
Excess Carbon ◽  
Controlling Elements ◽  
Tree Data ◽  
Microbacterium Paraoxydans ◽  
Coa Reductase ◽  
Beta Hydroxybutyrate

Bacterial poly-β-hydroxybutyrate (PHB) is a natural, biodegradable polymer, which is accumulated in the cells as an energy reserve materialdue to depletion of nitrogen or phosphorous in the presence of excess carbon source. This polymer is foreseen to possess high industrialpotentiality and excellent alternative to the non-degradable petroleum-based plastics. In this study, we isolated and characterized a localbacterial strain WA81 which accumulated 18mg/L PHB after 72 h growth in mineral salt medium under nitrogen deficiency. The PHB granuleswere detected in the cells using TEM and the genes encode for this polymer were detected by oligonucleotide primers using PCR technology.The 16S rRNA gene nucleotide sequence for this isolate was used to construct a phylogentic tree against all available sequences in the GenBank.The phylogenetic tree data suggested that the closest type strain to the local bacterium is the Microbacterium paraoxydans CF36T and hencewe named it Microbacterium sp. strain WA81. Moreover, the set of enzymes responsible for the PHB biosynthetic pathway and their controllingelements were detected in this local isolate using PCR. The genes encode for the biosynthesis enzymes are phbA (β-ketothiolase), phbB(acetoacetly CoA reductase), phbC (PHB polymerase), while the genes encode for the controlling elements are phbP (phasin), phbZ (PHBdepolymerase). The novelty of this local bacterium lies in its ability to accumulate huge amounts of PHB in its cytoplasm and the presence ofa whole set of genes encode for the PHB biosynthetic and catabolic pathways of this polymer.Int J Appl Sci Biotechnol, Vol 3(2): 143-150 DOI: http://dx.doi.org/10.3126/ijasbt.v3i2.12277 

Inhibition of protein geranylgeranylation induces apoptosis in myeloma plasma cells by reducing Mcl-1 protein levels

Blood ◽  
2003 ◽  
Vol 102 (9) ◽  
pp. 3354-3362 ◽  
Author(s):  
Niels W. C. J. van de Donk ◽  
Marloes M. J. Kamphuis ◽  
Berris van Kessel ◽  
Henk M. Lokhorst ◽  
Andries C. Bloem
Keyword(s):  
Multiple Myeloma ◽  
Plasma Cells ◽  
Mevalonate Pathway ◽  
Cytochrome C Release ◽  
Hmg Coa Reductase ◽  
Myeloma Cells ◽  
Protein Levels ◽  
Geranylgeranyl Transferase ◽  
Induced Apoptosis ◽  
Coa Reductase

AbstractHMG-CoA reductase is the rate-limiting enzyme of the mevalonate pathway leading to the formation of cholesterol and isoprenoids such as farnesylpyrophosphate (FPP) and geranylgeranylpyrophosphate (GGPP). The inhibition of HMG-CoA reductase by lovastatin induced apoptosis in plasma cell lines and tumor cells from patients with multiple myeloma. Here we show that cotreatment with mevalonate or geranylgeranyl moieties, but not farnesyl groups, rescued myeloma cells from lovastatin-induced apoptosis. In addition, the inhibition of geranylgeranylation by specific inhibition of geranylgeranyl transferase I (GGTase I) induced the apoptosis of myeloma cells. Apoptosis triggered by the inhibition of geranylgeranylation was associated with reduction of Mcl-1 protein expression, collapse of the mitochondrial transmembrane potential, expression of the mitochondrial membrane protein 7A6, cytochrome c release from mitochondria into the cytosol, and stimulation of caspase-3 activity. These results imply that protein geranylgeranylation is critical for regulating myeloma tumor cell survival, possibly through regulating Mcl-1 expression. Our results show that pharmacologic agents such as lovastatin or GGTase inhibitors may be useful in the treatment of multiple myeloma.

Metabolism of farnesyl diphosphate in tobacco BY-2 cells treated with squalestatin

2000 ◽  
Vol 28 (6) ◽  
pp. 794-796 ◽  
Author(s):  
M.-A. Hartmann ◽  
L. Wentzinger ◽  
A. Hemmerlin ◽  
T. J. Bach
Keyword(s):  
Mevalonate Pathway ◽  
Fold Increase ◽  
Enzymic Activity ◽  
Farnesyl Diphosphate ◽  
Allylic Alcohol ◽  
Central Position ◽  
Mrna Levels ◽  
Ubiquinone Q10 ◽  
Wide Range ◽  
Coa Reductase

Plant isoprenoids represent a large group of compounds with a wide range of physiological functions. In the cytosol, isoprenoids are synthesized via the classical acetate/mevalonate pathway. In this pathway, farnesyl diphosphate (FPP) occupies a central position, from which isoprene units are dispatched to the different classes of isoprenoids, with sterols as the major end products. The present work deals with effects of squalestatin (SQ) on the metabolism of FPP in proliferating and synchronized cultured tobacco cv. Bright Yellow-2 cells. SQ is a potent inhibitor of squalene synthase (SQS), the first committed enzyme in the sterol pathway. At nanomolar concentrations, SQ severely impaired cell growth and sterol biosynthesis, as attested by the rapid decrease in SQS activity. At the same time, it triggered a several-fold increase in both the enzymic activity and mRNA levels of 3-hydroxy-3-methylglutaryl CoA reductase. When SQ was added to cells synchronized by aphidicolin treatment, it was found to block the cell cycle at the end of G1 phase, but no cell death was induced. Tobacco cells were also fed exogenous tritiated trans-trans farnesol, the allylic alcohol derived from FPP, in the presence and absence of SQ. Evidence is presented that this compound was incorporated into sterols and ubiquinone Q10. In the presence of SQ, the sterol pathway was inhibited, but no increase in the radioactivity of ubiquinone was observed, suggesting that this metabolic channel was already saturated under normal conditions.

Altering potato isoprenoid metabolism increases biomass and induces early flowering

2020 ◽  
Vol 71 (14) ◽  
pp. 4109-4124
Author(s):  
Moehninsi ◽  
Iris Lange ◽  
B Markus Lange ◽  
Duroy A Navarre
Keyword(s):  
Metabolic Regulation ◽  
Transcriptional Control ◽  
Mevalonate Pathway ◽  
Early Flowering ◽  
Bioenergy Crops ◽  
Isoprenoid Metabolism ◽  
Transgenic Lines ◽  
Coa Reductase ◽  
Rate Limiting

Abstract Isoprenoids constitute the largest class of plant natural products and have diverse biological functions including in plant growth and development. In potato (Solanum tuberosum), the regulatory mechanism underlying the biosynthesis of isoprenoids through the mevalonate pathway is unclear. We assessed the role of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) homologs in potato development and in the metabolic regulation of isoprenoid biosynthesis by generating transgenic lines with down-regulated expression (RNAi-hmgr) or overexpression (OE) of one (StHMGR1 or StHMGR3) or two genes, HMGR and farnesyl diphosphate synthase (FPS; StHMGR1/StFPS1 or StHMGR3/StFPS1). Levels of sterols, steroidal glycoalkaloids (SGAs), and plastidial isoprenoids were elevated in the OE-HMGR1, OE-HMGR1/FPS1, and OE-HMGR3/FPS1 lines, and these plants exhibited early flowering, increased stem height, increased biomass, and increased total tuber weight. However, OE-HMGR3 lines showed dwarfism and had the highest sterol amounts, but without an increase in SGA levels, supporting a rate-limiting role for HMGR3 in the accumulation of sterols. Potato RNAi-hmgr lines showed inhibited growth and reduced cytosolic isoprenoid levels. We also determined the relative importance of transcriptional control at regulatory points of isoprenoid precursor biosynthesis by assessing gene–metabolite correlations. These findings provide novel insights into specific end-products of the sterol pathway and could be important for crop yield and bioenergy crops.

Lovastatin as Salvage Immunomodulatory Therapy in Patients with Refractory and Relapsed Multipla Myeloma.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1567-1567 ◽  
Author(s):  
Marek Hus ◽  
Norbert Grzasko ◽  
Dariusz Jawniak ◽  
Marta Szostek ◽  
Anna Dmoszynska
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Light Chain ◽  
Protein Level ◽  
Mevalonate Pathway ◽  
Sinus Bradycardia ◽  
Autologous Transplantation ◽  
M Protein ◽  
Hmg Coa Reductase ◽  
Coa Reductase

Abstract In the recent years the treatment of patients with multiple myeloma (MM) has changed because of the introduction of new agents, mainly thalidomide (THAL) and its derivatives and bortezomib, an inhibitor of the 20S proteasome. Lovastatin (LOV) and other inhibitors of HMG-CoA reductase, the rate-limiting enzyme of the mevalonate pathway, have been demonstrated to exibit antineoplasmatic and proapoptotic properties in numerous in vitro studies involving myeloma cell lines including our own experiments. This observation induced us to administer LOV in combination with THAL and dexamethasone (DEX). We report here our preliminary experiences with THAL and LOV therapy in patients with refractory and relapsed MM. We have treated 81 patients with THAL+DEX regimen (TD) or THAL+DEX+LOV regimen (TLD). Patients received drugs orally in 28 day cycles. THAL was given from day 1 to day 28 each cycle and it was started at a initial dose of 100 mg daily increased to 300 mg daily. DEX was administered at a dose of 40 mg daily in days 1–4 each cycle. LOV was administered at a dose of 2 mg/kg in days 1–5 and 8–12 and at a dose of 0.5 mg/kg in days 15–28 each cycle. TLD regimen was administered to 43 patients and TD regimen to 38 patients. Patients characteristics before treatment were as follows: the median age 61.2 years; 61% of patients IgG, 26% IgA, 7% light chain and 6% other; 76% of patients were light chain kappa and 24% lambda; median serum M-protein level was 4.2 g/dl, bone marrow plasma cells 47%, hemoglobin 10.1 g/dl, platelets 197 G/l, beta-2-microglobulin 4.2 mg/ml, albumin 3.9 g/dl and LDH 292 IU. The median follow-up was 29 month. A clinical response, defined as a reduction of M-protein level by 50% or more, was observed in 67.8% of patients in TD group and in 88.0% in TLD group. CR i NCR was observed in 35.0% and 62.7% respectively. In 11 TLD (25.5%.) and 4 TD (10.5%) patients successful stem cell harvest was performed and mean amount of collected CD34+ cells was 8.2*106/kg. Successful autologous transplantation was performed in 8 patients from this group. Overall survival in TLD group (median 23.0 months) was significantly longer than in TD group (median 18.0 months). Similarly event free survival was longer in TLD (median 7.0 months) group than in TD group (4.5 months). We observed significant negative correlation between response and bone marrow infiltration (p=0.008), M-protein level (p=0.0004) and positive correlation between response and albumin level (p=0.005). Short time to reduction of M-protein by 50% was connected with better response. Common side effects as somnolence, fatigue and constipation were observed in about 45% of patients in TLD and TD groups. In 2 TLD and in 3 TD patients we diagnosed deep vein thrombosis. In 2 TLD patients sinus bradycardia was observed. Our results suggest that addition of LOV to THAL and DEX improves response rate in patients with refactory and relapsed MM. Moreover it is possible to harvest stem cells and perform autologous stem cells graft in patients treated with such regimen. A future prospective randomised study is needed to confirm the value of LOV or other HMG-CoA reductase inhibitors in the treatment of MM patients.

Modulation of YAP/ TAZ by statins to improve survival in epithelioid hemangioendothelioma (EHE).

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. e23527-e23527
Author(s):  
Aparna Subramaniam ◽  
Jing Zheng ◽  
Sudha Yalamanchili ◽  
Anthony Paul Conley ◽  
Ravin Ratan ◽  
...  
Keyword(s):  
Mevalonate Pathway ◽  
Hippo Pathway ◽  
Nuclear Accumulation ◽  
Rank Test ◽  
Cancer Center ◽  
Hmg Coa Reductase ◽  
Number Of Patients ◽  
The Mean ◽  
Coa Reductase ◽  
Statin Use

e23527 Background: EHE is a rare soft tissue tumor of endothelial origin. It is distinguished by the pathognomonic WWTR1-CAMTA1 fusion (WWTR1 is the gene symbol for TAZ) seen in 90% of the tumors. YAP1-TFE3 fusion is less common and seen in 10% of the tumors. YAP and TAZ are critical downstream effectors of the Hippo pathway that regulate tumor development, progression, invasion and metastasis by modulating the expression of many Hippo pathway targets. Recent studies have shown that inhibition of HMG-CoA reductase, a key enzyme of the mevalonate pathway, can regulate YAP/ TAZ by preventing their nuclear accumulation and inhibiting their transcriptional activity. This has led to interest in the role of statins, which inhibit HMG-CoA reductase, as a modulator of YAP/ TAZ that could benefit patients with sarcoma, particularly EHE. Methods: A retrospective analysis was performed on patients with a diagnosis of EHE at M D Anderson Cancer Center. Patients were identified using the electronic database system and screened for statin use using EMRs. Demographic and clinical characteristics were tabulated. KM method was used to assess overall survival and log rank test was used to test survival differences between the statin use and non- statin use groups. All statistical analysis was performed using STATA 14. Results: 226 patients with EHE were identified. 27 of them had recorded statin use during the course of their disease. The median OS for the statin use group was not reached and the mean OS was 221 months. The median OS for the non- statin use group was 123.9 months, while the mean OS was 160 months. The difference in OS was not statistically significant between the two groups. The median follow-up time for our cohort was 36.6 months. Conclusions: Our findings indicate a trend towards improved survival for patients with EHE who have received statins over the course of their disease. Our study is limited by a small number of patients who received statins. Prospective studies are required to assess the therapeutic benefit of statins in EHE. [Table: see text]

scholarly journals Identification, Evolution, and Essentiality of the Mevalonate Pathway for Isopentenyl Diphosphate Biosynthesis in Gram-Positive Cocci

2000 ◽  
Vol 182 (15) ◽  
pp. 4319-4327 ◽  
Author(s):  
E. Imogen Wilding ◽  
James R. Brown ◽  
Alexander P. Bryant ◽  
Alison F. Chalker ◽  
David J. Holmes ◽  
...  
Keyword(s):  
Mevalonate Pathway ◽  
Genomic Analysis ◽  
Eukaryotic Cell ◽  
Infection Model ◽  
Isopentenyl Diphosphate ◽  
Gram Positive ◽  
Hmg Coa Reductase ◽  
Coa Reductase ◽  
Gram Positive Cocci

ABSTRACT The mevalonate pathway and the glyceraldehyde 3-phosphate (GAP)–pyruvate pathway are alternative routes for the biosynthesis of the central isoprenoid precursor, isopentenyl diphosphate. Genomic analysis revealed that the staphylococci, streptococci, and enterococci possess genes predicted to encode all of the enzymes of the mevalonate pathway and not the GAP-pyruvate pathway, unlike Bacillus subtilis and most gram-negative bacteria studied, which possess only components of the latter pathway. Phylogenetic and comparative genome analyses suggest that the genes for mevalonate biosynthesis in gram-positive cocci, which are highly divergent from those of mammals, were horizontally transferred from a primitive eukaryotic cell. Enterococci uniquely encode a bifunctional protein predicted to possess both 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and acetyl-CoA acetyltransferase activities. Genetic disruption experiments have shown that five genes encoding proteins involved in this pathway (HMG-CoA synthase, HMG-CoA reductase, mevalonate kinase, phosphomevalonate kinase, and mevalonate diphosphate decarboxylase) are essential for the in vitro growth of Streptococcus pneumoniae under standard conditions. Allelic replacement of the HMG-CoA synthase gene rendered the organism auxotrophic for mevalonate and severely attenuated in a murine respiratory tract infection model. The mevalonate pathway thus represents a potential antibacterial target in the low-G+C gram-positive cocci.

A Biosynthetic Pathway to Isovaleryl-CoA in Myxobacteria: The Involvement of the Mevalonate Pathway

ChemBioChem ◽  
2004 ◽  
Vol 6 (2) ◽  
pp. 322-330 ◽  
Author(s):  
Taifo Mahmud ◽  
Silke C. Wenzel ◽  
Eva Wan ◽  
Kwun Wah Wen ◽  
Helge B. Bode ◽  
...  
Keyword(s):  
Biosynthetic Pathway ◽  
Mevalonate Pathway

The deoxyxylulose phosphate pathway of isoprenoid biosynthesis. Discovery and function of the ispDEFGH genes and their cognate enzymes

2003 ◽  
Vol 75 (2-3) ◽  
pp. 393-405 ◽  
Author(s):  
F. Rohdich ◽  
Stefan Hecht ◽  
Adelbert Bacher ◽  
Wolfgang Eisenreich
Keyword(s):  
Biosynthetic Pathway ◽  
Mevalonate Pathway ◽  
Isoprenoid Biosynthesis ◽  
Catalytic Action ◽  
Isopentenyl Diphosphate ◽  
Dimethylallyl Diphosphate ◽  
And Function

Isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) serve as the universal precursors for the biosynthesis of terpenes. Besides the well-known mevalonate pathway, a second biosynthetic pathway conducive to IPP and DMAPP via 1-deoxy-d-xylulose-5-phosphate and 2C-methyl-d-erythritol-4-phosphate has been discovered recently in plants and certain eubacteria. 2C-Methyl-d-erythritol-4-phosphate, the first committed intermediate of the deoxyxylulose phosphate pathway, is converted into 2C-methyl-d-erythritol 2,4-cyclodiphosphate by the catalytic action of three enzymes specified by the ispDEF genes. The cyclic diphosphate is reductively opened by the IspG protein affording 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate. This compound can be converted into IPP as well as DMAPP by the catalytic action of IspH protein. The enzymes of this pathway are potential targets for novel antibacterial, antimalarial, and herbicide agents.

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