Sodium butyrate activates HMGCS2 to promote ketone body production through SIRT5-mediated desuccinylation / 医学前沿

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.

Proteomics of the colonic mucosa in sub-healthy people with shapeless stool / 中南大学学报(医学版)

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.

Mitochondrial Aldehyde Dehydrogenase Precursor Protein and 3-hydroxy-3-methylglutaryl-coenzyme A synthase 2: Two-dimensional Electrophoretic Expressed Protein in the Liver of Acute Alcoholic Abuse / 대한법의학회지

To study alcohol-related expressed proteins across postmortem livers, human liver tissues from two cadaveric subjects died of acute alcohol abuse and myocardialinfarct were compared. Liver tissues were separated by means of immobilized pH gradient- two-dimensional gel electrophoresis (2-DE) and Coomassie staining. Out of the differentially expressed proteins in 2-DE, four differential spots, which were strongly expressed in alcohol intoxication but faint in normal tissue, were selected and analyzed by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). Mass spectrometry (MS) analysis revealed these spots were mitochondrial aldehyde dehydrogenase precursor protein and 3-hydroxy-3-methylglutarylcoenzyme A synthase 2, respectively. Aldehyde dehydrogenase is the second-step enzyme for alcohol metabolism. 3-hydroxy-3-methylglutaryl-Coenzyme A synthase 2 is a key regulatory enzyme in the pathway for endogenous cholesterol synthesis. These preliminary data could suggest that the lipid metabolism-related protein as well as alcohol metabolic enzyme was expressed in acute alcohol abuse (binge drinking). Furthermore, it appears that proteomic tool would be applied for postmortem examination in the diagnosis of acute alcohol abuse

Expression, purification, characteristics and homology modeling of the HMGS from Streptococcus pneumoniae / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To 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).</p><p><b>METHODS</b>The genetic engineering technology and the composer module of SYBYL7.0 program were used, while the HMGS three-dimensional structure was analyzed by homology modeling.</p><p><b>RESULTS</b>The 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.</p><p><b>CONCLUSION</b>The 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.</p>

A controlled trial of pravastatin vs probucol in the treatment of primary hypercholesterolemia

Es un estudio comparativo de la seguridad, tolerabilidad y eficacia del inhibidor de HMGCoA reductasa, pravastatin, y probucol en el tratamiento de pacientes con hipercolesterolemia primaria, utilizando un diseño doble ciego, controlado con medicamento activo, con distribución aleatoria de los tratamientos, utilizando placebos de ambas drogas. Se incluyeron pacientes con LDL-C > de 150 mg/dL y triglicéridos < 350 mg/dL después de un mínimo de seis semanas recibiendo placebo y una dieta fase I de la American Heart Association. Los pacientes relacionados fueron asignados aleatoriamente para recibir pravastatin 40 mg diarios por la noche o probucol 500 mg cada 12 horas y también recibieron los placebos idénticos de las drogas en estudio. El periodo de tratamiento con medicación activa duró 16 semanas: durante este periodo, los pacientes fueron vistos a las 4, 8, 12 y 16 semanas. No se demostraron diferencias significativas entre los valores basales de ambos grupos. Los valores de colesterol total y LDL-C fueron significativamente menores con pravastatin que con probucol. Se observó un aumento promedio de HDL-C con pravastatin y probucol, fueron bien tolerados: sólo se observaron cambios clínicos y de laboratorio mínimos, ninguno de los cuales fue considerado relacionado con las drogas estudiadas. No se observaron cambios significativos en el cristalino. El estudio muestra una superioridad clara del pravastatin sobre el probucol basada en un cambio más favorable en el perfil de lípidos