Cell Line ; Cholesterol ; biosynthesis ; Hepatocytes ; drug effects ; metabolism ; Humans ; Hydroxymethylglutaryl-CoA Synthase ; metabolism ; Lipogenesis ; Quercetin ; pharmacology

Ketone bodies have beneficial metabolic activities, and the induction of plasma ketone bodies is a health promotion strategy. Dietary supplementation of sodium butyrate (SB) is an effective approach in the induction of plasma ketone bodies. However, the cellular and molecular mechanisms are unknown. In this study, SB was found to enhance the catalytic activity of 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2), a rate-limiting enzyme in ketogenesis, to promote ketone body production in hepatocytes. SB administrated by gavage or intraperitoneal injection significantly induced blood ß-hydroxybutyrate (BHB) in mice. BHB production was induced in the primary hepatocytes by SB. Protein succinylation was altered by SB in the liver tissues with down-regulation in 58 proteins and up-regulation in 26 proteins in the proteomics analysis. However, the alteration was mostly observed in mitochondrial proteins with 41% down- and 65% up-regulation, respectively. Succinylation status of HMGCS2 protein was altered by a reduction at two sites (K221 and K358) without a change in the protein level. The SB effect was significantly reduced by a SIRT5 inhibitor and in Sirt5-KO mice. The data suggests that SB activated HMGCS2 through SIRT5-mediated desuccinylation for ketone body production by the liver. The effect was not associated with an elevation in NAD⁺/NADH ratio according to our metabolomics analysis. The data provide a novel molecular mechanism for SB activity in the induction of ketone body production.
Mice ; Animals ; Butyric Acid/metabolism* ; Ketone Bodies/metabolism* ; Liver/metabolism* ; Hydroxybutyrates/metabolism* ; Down-Regulation ; Sirtuins/metabolism* ; Hydroxymethylglutaryl-CoA Synthase/metabolism*

3-hydroxy-3-methylgulutaryl-coenzyme A (HMG-CoA) reductase inhibitors or statins are a kind of lipid-lowering agents and have been used for the prevention and treatment of cardiovascular diseases. Recent studies suggested that statins, besides lowering cholesterol, may protect vessels by enhancing the activity of endothelial nitric oxide synthase (eNOS). In the present study, we investigated if simvastatin increases eNOS activity through its phosphorylation in 293 cells (293-eNOS) with stable expression of eNOS. The results showed that incubation of 293-eNOS cells with simvastatin (10 microm/L) for 2 h significantly increased in the activity of eNOS as shown by the conversion of L-arginine to L-citrulline (2889.70+/-201.51 versus 5630.18+/-218.75 pmol/min . mg proteins) (P<0.01). Western blotting revealed that simvastatin increased phosphorylation of eNOS at 1177 (ser) and also 495 (thr) but did not affect the overall expression of eNOS or inducible NOS. Further study found that simvastatin raised phosphorylation levels of Akt and AMPK, and such effect could be antagonized by Akt inhibitor or AMPK inhibitor. These results suggest that simvastatin could stimulate the activity of eNOS via its phosphorylation by Akt and AMPK, which provides a new mechanism, other than lipid-lowering effect, for the cardiovascular protection of statins.
Cell Line ; Epithelial Cells/cytology ; Epithelial Cells/*enzymology ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/*pharmacology ; Kidney/*cytology ; Nitric Oxide Synthase Type III/*metabolism ; Phosphorylation ; Simvastatin/*pharmacology

Blood Platelets ; enzymology ; Diabetes Mellitus, Type 2 ; enzymology ; Enzyme Activation ; Humans ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; pharmacology ; Nitric Oxide Synthase ; metabolism ; Nitric Oxide Synthase Type III ; Phosphorylation ; Pravastatin ; pharmacology ; Serine ; metabolism

Amino Acid Metabolism, Inborn Errors ; diagnosis ; genetics ; therapy ; Death, Sudden ; etiology ; Hereditary Central Nervous System Demyelinating Diseases ; diagnosis ; etiology ; Humans ; Hydroxymethylglutaryl-CoA Synthase ; deficiency ; Infant, Newborn ; Male ; Mutation ; Oxo-Acid-Lyases ; genetics ; Spectrometry, Mass, Electrospray Ionization ; Tandem Mass Spectrometry

OBJECTIVETo understand the molecular basis for a potential reaction mechanism and develop novel antibiotics with homology modeling for 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase (HMGS).

METHODSThe genetic engineering technology and the composer module of SYBYL7.0 program were used, while the HMGS three-dimensional structure was analyzed by homology modeling.

RESULTSThe mvaS gene was cloned from Streptococcus pneumoniae and overexpressed in Escherichia coli from a pET28 vector. The expressed enzyme (about 46 kDa) was purified by affinity chromatography with a specific activity of 3.24 micromol/min/mg. Optimal conditions were pH 9.75 and 10 mmol/L MgCl2 at 37 degrees C. The V(max) and K(m) were 4.69 micromol/min/mg and 213 micromol/L respectively. The 3D model of S. pneumoniae HMGS was established based on structure template of HMGS of Enterococcus faecalis.

CONCLUSIONThe structure of HMGS will facilitate the structure-based design of alternative drugs to cholesterol-lowering therapies or to novel antibiotics to the Gram-positive cocci, whereas the recombinant HMGS will prove useful for drug development against a different enzyme in the mevalonate pathway.

Amino Acid Sequence ; Base Sequence ; Cloning, Molecular ; Gene Expression Regulation, Bacterial ; physiology ; Hydroxymethylglutaryl-CoA Synthase ; chemistry ; genetics ; metabolism ; Models, Molecular ; Molecular Sequence Data ; Mutation ; Protein Conformation ; Streptococcus pneumoniae ; enzymology ; genetics

OBJECTIVE: To establish the 2-dimensional electrophoresis (2-DE) map in colonic mucosa in sub-healthy people with shapeless stool and healthy people, to identify the differential proteins by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS), and to provide theoretical basis for the pathogenesis of intestinal mucosa in sub-healthy people with shapeless stool. METHODS: Two-DE was used to separate the total proteins from the intestinal mucosa in sub-healthy people (the sub-health group) with the shapeless stool and healthy volunteers (the control group). ImageMaster 2D Elite soft was applied to analyze the 2-DE images, and the differentially expressed protein spots between the 2 groups were identified by MALDI-TOF-MS, protein bank and information technique. RESULTS: We analyzed the average maps and obtained 517 protein spots in the sub-healthy group and 535 protein spots in the control group. Between the sub-healthy group and the control group, the mean of 366 protein spots was matched, and the matching rate was 70.79%. Ten differential protein spots were screened by MALDI-TOF-MS, and 8 were identified. Five out of the 8 spots were significantly decreased, while 3 out of the 8 were significantly increased. CONCLUSION The proteomic expression in colonic mucosa of people with shapeless stool is significantly different from that of healthy people. Eight differential proteins such as aldehyde dehydrogenase 1A1 isoform 1, 3-hydroxy-3-methylglutaryl-coenzyme A synthase 2 (mitochondrial), γ-actin, annexin A5 possibly involve in the pathogenesis of sub-healthy people with shapeless stool.
Actins ; metabolism ; Aldehyde Dehydrogenase ; metabolism ; Aldehyde Dehydrogenase 1 ; Annexin A5 ; metabolism ; Case-Control Studies ; Colon ; metabolism ; physiopathology ; Dyspepsia ; metabolism ; Electrophoresis, Gel, Two-Dimensional ; Female ; Humans ; Hydroxymethylglutaryl-CoA Synthase ; metabolism ; Intestinal Mucosa ; metabolism ; physiopathology ; Male ; Proteins ; genetics ; isolation & purification ; metabolism ; Proteome ; analysis ; Proteomics ; methods ; Retinal Dehydrogenase

Hypertension is associated with endothelial dysfunction and increased cardiovascular risk. Caveolin-1 regulates nitric oxide (NO) signaling by modulating endothelial nitric oxide synthase (eNOS). The purpose of this study was to examine whether HMG-CoA reductase inhibitor improves impaired endothelial function of the aorta in spontaneous hypertensive rat (SHR) and to determine the underlying mechanisms involved. Eight-week-old male SHR were assigned to either a control group (CON, n=11) or a rosuvastatin group (ROS, n=12), rosuvastatin (10 mg/kg/day) administered for eight weeks. Abdominal aortic rings were prepared and responses to acetylcholine (10-9-10-4 M) were determined in vitro. To evaluate the potential role of NO and caveolin-1, we examined the plasma activity of NOx, eNOS, phosphorylated-eNOS and expression of caveolin-1. The relaxation in response to acetylcholine was significantly enhanced in ROS compared to CON. Expression of eNOS RNA was unchanged, whereas NOx level and phosphorylated-eNOS at serine-1177 was increased accompanied with depressed level of caveolin-1 in ROS. We conclude that 3-Hydroxy-3-methylglutaryl Coenzyme-A (HMG-CoA) reductase inhibitor can improve impaired endothelial dysfunction in SHR, and its underlying mechanisms are associated with increased NO production. Furthermore, HMG-CoA reductase inhibitor can activate the eNOS by phosphorylation related to decreased caveolin-1 abundance. These results imply the therapeutic strategies for the high blood pressure-associated endothelial dysfunction through modifying caveolin status.
Acetylcholine/metabolism ; Animals ; Aorta/metabolism/physiopathology ; Blood Pressure/drug effects ; Caveolin 1/*metabolism ; Down-Regulation ; Drug Administration Schedule ; Endothelium, Vascular/*drug effects/physiopathology ; Fluorobenzenes/administration & dosage/*pharmacology ; Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage/*pharmacology ; Hypertension/enzymology/metabolism/*physiopathology ; Male ; Nitric Oxide/blood ; Nitric Oxide Synthase Type III/*metabolism ; Phosphorylation ; Pyrimidines/administration & dosage/*pharmacology ; Rats ; Rats, Inbred SHR ; Sulfonamides/administration & dosage/*pharmacology ; Vasodilation/drug effects

OBJECTIVEto investigate the combined effect of rosuvastatin (RSV) and ischemic postconditioning (PC) on myocardial ischemia-reperfusion (I/R) injury in a type 2 diabetic rat model.

METHODStype 2 diabetic (induced by streptozotocin plus nicotinamide) rats, undergoing 30 min ischemia and 120 min reperfusion, were divided into six groups (n = 10 each): Sham, I/R without other interventions, RSV before reperfusion, PC with 3 cycles of 10 s reperfusion and 10 s ischemia, RSV + PC and RSV + PC + PI3-K inhibitor LY294002. Myocardial infarct size (IS), ultrastructural change and myocardial expression of phosphorylated eNOS/total eNOS were determined.

RESULTSIS and ultrastructural damages were all significantly reduced and myocardial eNOS phosphorylation was significantly increased in RSV and PC groups compared with the I/R group (all P < 0.05) these beneficial effects were further enhanced by RSV + PC (all P < 0.05 vs. RSV and PC, respectively). The beneficial effects were significantly attenuated by PI3K inhibitor LY294002.

CONCLUSIONSthe results indicate that RSV + PC could alleviate myocardial ischemia-reperfusion injury in this type 2 diabetic model by activating PI3K/AKT/eNOS signaling pathway.

Animals ; Diabetes Mellitus, Experimental ; complications ; Diabetes Mellitus, Type 2 ; complications ; Fluorobenzenes ; pharmacology ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; pharmacology ; Ischemic Postconditioning ; Male ; Myocardial Reperfusion Injury ; prevention & control ; Myocardium ; pathology ; ultrastructure ; Nitric Oxide Synthase Type III ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Phosphorylation ; Proto-Oncogene Proteins c-akt ; metabolism ; Pyrimidines ; pharmacology ; Rats ; Rats, Wistar ; Rosuvastatin Calcium ; Signal Transduction ; Sulfonamides ; pharmacology