scholarly journals Bark Extracts of Ceylon Cinnamon Possess Antilipidemic Activities and Bind Bile Acids In Vitro

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Walimuni Prabhashini Kaushalya Mendis Abeysekera ◽  
Sirimal Premakumara Galbada Arachchige ◽  
Wanigasekera Daya Ratnasooriya
Keyword(s):  
Bile Acids ◽  
Scientific Evidence ◽  
Ethanol Extract ◽  
Cholesterol Esterase ◽  
Hmg Coa Reductase ◽  
Cinnamon Bark ◽  
Ceylon Cinnamon ◽  
Inhibitory Activities ◽  
Coa Reductase

Ethanol (95%) and dichloromethane : methanol (1 : 1) bark extracts of authenticated Ceylon cinnamon were investigated for range of antilipidemic activities (ALA): HMG-CoA reductase, lipase, cholesterol esterase, and cholesterol micellization inhibitory activities and bile acids binding in vitro. Individual compounds in bark extracts were also evaluated. Bark extracts showed ALA in all the assays studied. The IC50 (μg/mL) values ranged within 153.07±8.38–277.13±32.18, 297.57±11.78–301.09±4.05, 30.61±0.79–34.05±0.41, and 231.96±9.22–478.89±9.27, respectively, for HMG-CoA reductase, lipase, cholesterol esterase, and cholesterol micellization inhibitory activities. The bile acids binding (3 mg/mL) for taurocholate, glycodeoxycholate, and chenodeoxycholate ranged within 19.74±0.31–20.22±0.31, 21.97±2.21–26.97±1.61, and 16.11±1.42–19.11±1.52%, respectively. The observed ALA were moderate compared to the reference drugs studied. Individual compounds in bark extracts ranged within 2.14±0.28–101.91±3.61 and 0.42±0.03–49.12±1.89 mg/g of extract. Cinnamaldehyde and gallic acid were the highest and the lowest among the tested compounds. The ethanol extract had highest quantity of individual compounds and ALA investigated. Properties observed indicate usefulness of Ceylon cinnamon bark in managing hyperlipidemia and obesity worldwide. Further, this study provides scientific evidence for the traditional claim that Ceylon cinnamon has antilipidemic activities.

In vitro antioxidant, antiglycation, and enzymatic inhibitory activity against α-glucosidase, α-amylase, lipase and HMG-CoA reductase of Terminalia boivinii Tul.

2021 ◽  
pp. 102235
Author(s):  
Bongani Sicelo Dlamini ◽  
Carlos Eduardo Hernandez ◽  
Chiy-Rong Chen ◽  
Wen-Ling Shih ◽  
Jue-Liang Hsu ◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
Hmg Coa Reductase ◽  
Coa Reductase

scholarly journals An autonomous, but INSIG-modulated, role for the Sterol Sensing Domain in mallostery-regulated ERAD of yeast HMG-CoA reductase

2020 ◽  
pp. jbc.RA120.015910
Author(s):  
Margaret A Wangeline ◽  
Randolph Y Hampton
Keyword(s):  
Binding Site ◽  
Quaternary Structure ◽  
Limited Proteolysis ◽  
Hmg Coa Reductase ◽  
Coa Reductase ◽  
Level Analysis

HMG-CoA reductase (HMGR) undergoes feedback-regulated degradation as part of sterol pathway control. Degradation of the yeast HMGR isozyme Hmg2 is controlled by the sterol pathway intermediate GGPP, which causes misfolding of Hmg2, leading to degradation by the HRD pathway; we call this process mallostery. We evaluated the role of the Hmg2 sterol sensing domain (SSD) in mallostery, as well as the involvement of the highly conserved INSIG proteins. We show that the Hmg2 SSD is critical for regulated degradation of Hmg2 and required for mallosteric misfolding of GGPP as studied by in vitro limited proteolysis. The Hmg2 SSD functions independently of conserved yeast INSIG proteins, but its function was modulated by INSIG, thus imposing a second layer of control on Hmg2 regulation. Mutant analyses indicated that SSD-mediated mallostery occurred prior to and independent of HRD-dependent ubiquitination. GGPP-dependent misfolding was still extant but occurred at a much slower rate in the absence of a functional SSD, indicating that the SSD facilitates a physiologically useful rate of GGPP response, and implying that the SSD is not a binding site for GGPP. Non-functional SSD mutants allowed us to test the importance of Hmg2 quaternary structure in mallostery:  a non-responsive Hmg2 SSD mutant strongly suppressed regulation of a co-expressed, normal Hmg2. Finally, we have found that GGPP-regulated misfolding occurred in detergent-solubilized Hmg2, a feature that will allow next-level analysis of the mechanism of this novel tactic of ligand-regulated misfolding.

scholarly journals Crude Ethanol Extract ofPithecellobium ellipticumas a Potential Lipid-Lowering Treatment for Hypercholesterolaemia

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Janet P.-C. Wong ◽  
Sumi Wijaya ◽  
Kang-Nee Ting ◽  
Christophe Wiart ◽  
Kamarul’Ain Mustafa ◽  
...  
Keyword(s):  
Antioxidant Properties ◽  
Ethanol Extract ◽  
Beta Carotene ◽  
The Other ◽  
Lipid Lowering ◽  
Hmg Coa Reductase ◽  
Atherosclerosis Progression ◽  
Bioactive Fraction ◽  
Responsible Group ◽  
Coa Reductase

If left untreated, hypercholesterolaemia can lead to atherosclerosis, given time. Plants from the Fabaceae family have shown the ability to significantly suppress atherosclerosis progression. We selected four extracts fromPithecellobium ellipticum, from the Fabaceae family, to be screened in a 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) assay. The ethanol extract, at a concentration of 500 μg/mL, exhibited superior inhibition properties over the other extracts by demonstrating 80.9% inhibition, while 0.223 μg/mL of pravastatin (control) showed 78.1% inhibition towards enzymatic activity. These findings led to the fractionation of the ethanol extract using ethyl acetate : methanol (95 : 5), gradually increasing polarity and produced seven fractions (1A to 7A). Fraction 7A at 150 μg/mL emerged as being the most promising bioactive fraction with 78.7% inhibition. FRAP, beta carotene, and DPPH assays supported the findings from the ethanol extract as it exhibited good overall antioxidant activity. The antioxidant properties have been said to reduce free radicals that are able to oxidize lipoproteins which are the cause of atherosclerosis. Phytochemical screenings revealed the presence of terpenoid, steroid, flavonoid, and phenolic compounds as the responsible group of compound(s), working individually or synergistically, within the extract to prevent binding of HMG-CoA to HMG-CoA reductase.

Bile duct cells: a novel in vitro model for the study of lipid metabolism and bile acid production

1999 ◽  
Vol 276 (2) ◽  
pp. G407-G414 ◽  
Author(s):  
Monika Zoltowska ◽  
Edgard E. Delvin ◽  
Khazal Paradis ◽  
Ernest Seidman ◽  
Emile Levy
Keyword(s):  
Bile Acid ◽  
Bile Duct ◽  
Bile Acids ◽  
Cytokeratin 19 ◽  
Sterol Metabolism ◽  
Hmg Coa Reductase ◽  
Biliary Epithelium ◽  
Duct Cells ◽  
Coa Reductase

Immortalized bile duct cells (BDC), derived from transgenic mice harboring the SV40 thermosensitive immortalizing mutant gene ts458, were utilized to investigate the role of the biliary epithelium in lipid and sterol metabolism. This cell model closely resembles the in vivo situation because it expresses the specific phenotypic marker cytokeratin 19 (CK-19), exhibits the formation of bile duct-like structures, and displays well-formed microvilli projected from the apical side to central lumen. The BDC were found to incorporate [14C]oleic acid (in nmol/mg protein) into triglycerides (121 ± 6), phospholipids (PL; 59 ± 3), and cholesteryl ester (16 ± 1). The medium lipid content represented 5.90 ± 0.16% ( P < 0.005) of the total intracellular production, indicating a limited lipid export capacity. Analysis of PL composition demonstrated the synthesis of all classes of polar lipids, with phosphatidylcholine and phosphatidylethanolamine accounting for 60 ± 1 and 24 ± 1%, respectively, of the total. Differences in PL distribution were apparent between cells and media. Substantial cholesterol synthesis was observed in BDC, as determined by the incorporation of [14C]acetate suggesting the presence of hydroxymethylglutaryl-CoA (HMG-CoA) reductase, the rate-limiting enzyme in the cholesterol biosynthetic pathway. With the use of [14C]acetate and [14C]cholesterol as precursors, both tauro- and glycoconjugates of bile acids were synthesized, indicating the presence of cholesterol 7α- and 26R-hydroxylases, the key enzymes involved in bile acid formation. The transport of bile acids was not limited, as shown by their marked accumulation in the medium (>6-fold of cell content). HMG-CoA reductase (53.0 ± 6.7), cholesterol 7α-hydroxylase (15.5 ± 0.5), and acyl-CoA:cholesterol acyltransferase (ACAT; 201.7 ± 10.2) activities (in pmol ⋅ min−1 ⋅ mg protein−1) were present in the microsomal fractions. Our data show that biliary epithelial cells actively synthesize lipids and may directly contribute bile acids to the biliary fluid in vivo. This BDC line thus represents an efficient experimental tool to evaluate biliary epithelium sterol metabolism and to study biliary physiology.

scholarly journals An HMG-CoA Reductase Inhibitor, Cerivastatin, Suppresses Growth of Macrophages Expressing Matrix Metalloproteinases and Tissue Factor In Vivo and In Vitro

Circulation ◽  
2001 ◽  
Vol 103 (2) ◽  
pp. 276-283 ◽  
Author(s):  
Masanori Aikawa ◽  
Elena Rabkin ◽  
Seigo Sugiyama ◽  
Sami J. Voglic ◽  
Yoshihiro Fukumoto ◽  
...  
Keyword(s):  
Matrix Metalloproteinases ◽  
Tissue Factor ◽  
Reductase Inhibitor ◽  
Hmg Coa Reductase ◽  
Hmg Coa Reductase Inhibitor ◽  
Coa Reductase

scholarly journals The Effects of Boron Derivatives on Lipid Absorption from the Intestine and on Bile Lipids and Bile Acids of Sprague Dawley Rats

1995 ◽  
Vol 2 (2) ◽  
pp. 65-72 ◽  
Author(s):  
Iris H. Hall ◽  
David J. Reynolds ◽  
O. T. Wong ◽  
A. Sood ◽  
B. F. Spielvogel
Keyword(s):  
Bile Acids ◽  
Intestinal Mucosa ◽  
Enzyme Activities ◽  
Reductase Activity ◽  
Lipid Absorption ◽  
Small Intestinal Mucosa ◽  
Acyl Transferase ◽  
Hmg Coa Reductase ◽  
Small Intestinal ◽  
Coa Reductase

N,N-dimethyl-n-octadecylamine borane 1¯ at 8 mg/kg/day, tetrakis-u-(trimethylamine boranecarboxylato)-bis(trimethyl-carboxyborane)-dicopper(II) 2¯ at 2.5 mg/kg/day and trimethylamine-carboxyborane 3¯ at 8 mg/kg/day were evaluated for their effects on bile lipids, bile acids, small intestinal absorption of cholesterol and cholic acid and liver and small intestinal enzyme activities involved in lipid metabolism. The agent administered orally elevated rat bile excretion of lipids, e.g. cholesterol and phospholipids, and compounds 2¯ and 3¯ increased the bile flow rate. These agents altered the composition of the bile acids, but there was no significant increase in lithocholic acid which is most lithogenic agent in rats. The three agents did decrease cholesterol absorption from isolated in situ intestinal duodenum loops in the presence of drug. Hepatic and small intestinal mucosa enzyme activities, e.g. ATP-dependent citrate lyase, acyl CoA cholesterol acyl transferase, cholsterol-7-α -hydroxylase, sn glycerol-3-phosphate acyl transferase, phosphatidylate phosphohydrolase, and lipoprotein lipase, were reduced. However, the boron derivatives 1¯ and 3¯ decreased hepatic HMG-CoA reductase activity, the regulatory enzyme for cholesterol synthesis, but the compounds had no effects on small intestinal mucosa HMG-CoA reductase activity. There was no evidence of hepatic cell damage afforded by the drugs based on clinical chemistry values which would induce alterations in bile acid concentrations after treatment of the rat.

scholarly journals Molecular cloning and sequence of a cholesterol-repressible enzyme related to prenyltransferase in the isoprene biosynthetic pathway.

1987 ◽  
Vol 7 (9) ◽  
pp. 3138-3146 ◽  
Author(s):  
C F Clarke ◽  
R D Tanaka ◽  
K Svenson ◽  
M Wamsley ◽  
A M Fogelman ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Molecular Cloning ◽  
In Vitro Transcription ◽  
In Vitro Translation ◽  
Mrna Levels ◽  
Hmg Coa Reductase ◽  
Transcription System ◽  
Coa Reductase

Differential hybridization and molecular cloning have been used to isolate CR39, a cDNA which hybridizes to a 1.2-kilobase (kb) mRNA in rat liver. The level of CR39 mRNA was increased seven- to ninefold over normal levels by dietary cholestyramine and mevinolin and decreased about fourfold compared with normal levels by cholesterol feeding or administration of mevalonate. Similar changes in the mRNA levels of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and HMG-CoA synthase were observed under the various conditions. In vitro translation of either CR39 hybrid selected RNA or 1.2-kb CR39 RNA generated by an SP6 in vitro transcription system produced a polypeptide of 39,000 daltons. As deduced from the nucleotide sequence of a full-length CR39 cDNA, the rat CR39 polypeptide contained 344 amino acids and had a molecular weight of 39,615. The predicted amino acid composition and submit molecular weight of the rat CR39 were very similar to those of prenyltransferases isolated from chicken, pig, and human. The sequence of amino acid residues 173 through 203 in the rat CR39 polypeptide showed that 17 out of 30 matched an active-site peptide of avian liver prenyltransferase. Thus, alterations in the rate of cholesterogenesis resulted in the coordinate regulation of three mRNAs encoding HMG-CoA reductase, HMG-CoA synthase, and CR39, the latter being tentatively identified as prenyltransferase.

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.

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