scholarly journals Inhibitory Effect onIn VitroLDL Oxidation and HMG Co-A Reductase Activity of the Liquid-Liquid Partitioned Fractions ofHericium erinaceus(Bull.) Persoon (Lion’s Mane Mushroom)

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Mohammad Azizur Rahman ◽  
Noorlidah Abdullah ◽  
Norhaniza Aminudin
Keyword(s):  
Therapeutic Potential ◽  
Reductase Activity ◽  
Antioxidant Properties ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Inhibitory Effect ◽  
Hexane Fraction ◽  
Ldl Oxidation ◽  
Hericium Erinaceus

Oxidation of low-density lipoprotein (LDL) has been strongly suggested as the key factor in the pathogenesis of atherosclerosis. Mushrooms have been implicated in having preventive effects against chronic diseases due especially to their antioxidant properties. In this study,in vitroinhibitory effect ofHericium erinaceuson LDL oxidation and the activity of the cholesterol biosynthetic key enzyme, 3-hydroxy-3-methyl glutaryl coenzyme A (HMG Co-A) reductase, was evaluated using five liquid-liquid solvent fractions consisting of methanol : dichloromethane (M : DCM), hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), and aqueous residue (AQ). The hexane fraction showed the highest inhibition of oxidation of human LDL as reflected by the increased lag time (100 mins) for the formation of conjugated diene (CD) at 1 µg/mL and decreased production (68.28%, IC500.73 mg/mL) of thiobarbituric acid reactive substances (TBARS) at 1 mg/mL. It also mostly inhibited (59.91%) the activity of the HMG Co-A reductase at 10 mg/mL. The GC-MS profiling of the hexane fraction identified the presence of myconutrients:inter alia, ergosterol and linoleic acid. Thus, hexane fraction ofHericium erinaceuswas found to be the most potentin vitroinhibitor of both LDL oxidation and HMG Co-A reductase activity having therapeutic potential for the prevention of oxidative stress-mediated vascular diseases.

scholarly journals Inhibition of in vitro macrophage-induced low density lipoprotein oxidation by thyroid compounds

2003 ◽  
Vol 177 (1) ◽  
pp. 137-146 ◽  
Author(s):  
L Oziol ◽  
P Faure ◽  
N Bertrand ◽  
P Chomard
Keyword(s):  
Cell Viability ◽  
Antioxidant Capacity ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Human Monocyte ◽  
Ldl Oxidation ◽  
Low Density ◽  
Redox Systems

Oxidized low density lipoproteins (LDL) are highly suspected of initiating the atherosclerosis process. Thyroid hormones and structural analogues have been reported to protect LDL from lipid peroxidation induced by Cu2+ or the free radical generator 2,2'-azobis-'2-amidinopropane' dihydrochloride in vitro. We have examined the effects of thyroid compounds on macrophage-induced LDL oxidation. Human monocyte-derived macrophages (differentiated U937 cells) were incubated for 24 h with LDL and different concentrations (0-20 microM) of 3,5,3'-triiodo-l -thyronine (T3), 3,5,3',5'-tetraiodo-L-thyronine (T4), 3,3',5'-tri-iodo-l -thyronine (rT3), the T3 acetic derivative (3,5,3'-tri-iodothyroacetic acid; TA3) or L-thyronine (T0) (experiment 1). Cells were also preincubated for 24 h with 1 or 10 microM of the compounds, washed twice, then incubated again for 24 h with LDL (experiment 2). Oxidation was evaluated by measurement of thiobarbituric acid-reactive substances (TBARS) and cell viability by lactate deshydrogenase release. In experiment 1, T0 had no effect, whereas the other compounds decreased LDL TBARS production, but T3 and TA3 were less active than T4 and rT3 (IC50: 11.0 +/- 2.6 and 8.1 +/- 0.8 vs 1.4 +/- 0.5 and 0.9 +/- 0.3 microM respectively). In experiment 2, the compounds at 1 microM had no effect; at 10 microM, T3 and rT3 slightly reduced LDL TBARS production, whereas TA3 and T4 inhibited it by about 50% and 70% respectively. TBARS released by the cells were also highly decreased by T3, T4, rT3 and TA3 in experiment 1, but only by T3 (30%) and T4 (70%) in experiment 2. Cell viability was not affected by the compounds except slightly by TA3 at 10 microM. The data suggested that the physico-chemical antioxidant capacity of thyroid compounds was modulated by their action on the intracellular redox systems of macrophage. Overall cellular effects of T3 led to a reduction of its antioxidant capacity whereas those of T4 increased it. Thus T4 might protect LDL against cellular oxidation in vivo more than T3.

scholarly journals In vitro antioxidant activity of meniran (Phyllantus urinaria) functional drink in human low density lipoprotein (LDL)

2021 ◽  
Vol 913 (1) ◽  
pp. 012093
Author(s):  
U Fitrotin ◽  
N Hilmiati ◽  
Mardiana ◽  
Y Triguna ◽  
A Surahman ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Phenolic Content ◽  
Radical Scavenging Activity ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Density Lipoprotein ◽  
Ldl Oxidation ◽  
Functional Drink

Abstract Preparation process for meniran (Phillantus urinaria) functional drink (MFD) influences its antioxidant activity. This research aims to understand the phenolic content, DPPH Radical Scavenging Activity (RSA), and LDL oxidation of MFD through various preparation processes. Those preparation processes included soaking fresh meniran (SFM), boiling fresh meniran for 5 minutes (BFM5’), boiling fresh meniran for 10 minutes (BFM10’), and soaking dried meniran (DM). The phenolic content was determined with Folin–Ciocalteu, antioxidant activity was assessed using DPPH and TBARS assay with LDL as the oxidation substrate. An antioxidant references in this research used ascorbic acid. The phenolic content in methods of SFM, BFM5’, BFM10’ and DM were 122±0.022, 182±0.043, 192 ±0.03, and 117 ±0.019 mg GAE/g of meniran respectively. Meanwhile, the DPPH RSA of SFM, BFM5’, BFM10’ and DM accounted for 82.18±0.35, 86.19±0.53, 86.75±0.64 and 69.96% respectively. As comparison, the DPPH RSA of ascorbic acid 50 ppm is 75.65±0.82%. At the same time the optimum inhibition of TBARS formation from BFM5’ and BFM10’ methods were 45.83 % and 48.66%, with MDA concentration in human LDL accounted for 38.30±2.39 and 36.30±1.82 nmol MDA/mg protein, respectively. As comparison, MDA concentration in human LDL added with ascorbic acid 25 ppm accounted for 41.35±2.41 nmol MDA/mg protein. In contrast, the control human LDL was 70.70±2.35 nmol MDA/mg protein. This study concludes that the BFM5’ and BFM10’ methods showed the highest antioxidant properties compared to other methods. All methods showed that MFD extract in concentration more than 25 ppm increased the concentration of MDA in human LDL. Therefore, to produce meniran functional drink in optimum antioxidant properties is best by using BFM5’ and BFM10’ preparation methods in meniran concentration of not more than 25 ppm.

Improved Measurement of Low-Density-Lipoprotein Susceptibility to Copper-Induced Oxidation: Application of a Short Procedure for Isolating Low-Density Lipoprotein

1992 ◽  
Vol 38 (10) ◽  
pp. 2066-2072 ◽  
Author(s):  
H A Kleinveld ◽  
H L Hak-Lemmers ◽  
A F Stalenhoef ◽  
P N Demacker
Keyword(s):  
Low Density Lipoprotein ◽  
Atherosclerotic Lesion ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Lag Time ◽  
Butylated Hydroxytoluene ◽  
Ldl Oxidation ◽  
Low Density ◽  
Short Run

Abstract Low-density-lipoprotein (LDL) oxidation may provide the crucial link between plasma LDL and atherosclerotic-lesion formation. Oxidation can be induced in vitro by incubating LDL with cells or metal ions and can be measured by continuously monitoring conjugated-diene absorbance at 234 nm. Measurement of LDL oxidizability was improved by performing the assay with 0.05 g of LDL-protein per liter of phosphate buffer containing 1 mumol of EDTA, by initiating oxidation by adding CuCl2 (5 mumol/L) at 30 degrees C, and by using a short-run ultracentrifugation method for isolating LDL, which reduced the time needed for obtaining purified LDL and thus reduced in vitro oxidation. LDL apolipoprotein analysis and oxidizability determination showed that this method is better than the longer sequential-isolation procedure. Adding butylated hydroxytoluene (BHT) to plasma as an antioxidant unpredictably increased the LDL oxidation lag time, making BHT unsuitable as an antioxidant. Adding EDTA appeared to be sufficient to prevent in vitro oxidation. Additionally, the diene production correlated highly with the concentration of thiobarbituric acid-reactive substances (r = 0.97). No relation between the vitamin E content of LDL and the oxidation lag time was found.

Effect of Curcumin on LDL Oxidation in Vitro, and Lipid Peroxidation and Antioxidant Enzymes in Cholesterol Fed Rabbits

2011 ◽  
Vol 81 (6) ◽  
pp. 378-391 ◽  
Author(s):  
M. Mahfouz ◽  
Zhou ◽  
A. Kummerow
Keyword(s):  
Low Density Lipoprotein ◽  
Plasma Lipid ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Ldl Oxidation ◽  
Control Group ◽  
Liver Lipids ◽  
Pure Cholesterol

In this study we examined the antioxidant effect of curcumin on lipid oxidation in vitro and in vivo. In vitro, curcumin at 5 microgM concentration completely prevented low-density lipoprotein (LDL) oxidation by CuS04, indicating that curcumin is an effective antioxidant in vitro. In vivo, feeding a pure cholesterol (PC)-rich diet to rabbits significantly increased the plasma and liver lipids as well as thiobarbituric acid reactive substances (TBARS) levels. Addition of curcumin to the PC diet did not show any effect on either plasma lipid and TBARS or liver lipids. Liver TBARS tended to decrease but that decrease was not significant. Erythrocyte glutathione peroxidase (GSH-Px) activity was significantly decreased while catalase activity was significantly increased in rabbits fed a PC diet. The addition of curcumin to a PC diet did not show any significant effect on erythrocyte enzyme activities compared to the rabbits fed a PC diet. The liver GSH-Px and catalase activities were significantly decreased in rabbits fed a PC diet, but the addition of curcumin to the PC diet enhanced the liver GSH-Px activity, which became nonsignificantly different from the control group. These results were discussed considering that curcumin may not be well absorbed and it did not reach a level high enough in vivo to overcome the severe hypercholesterolemia and oxidative stress produced by the PC-rich diet.

scholarly journals Epimedium koreanum Extract and Its Flavonoids Reduced Atherosclerotic Risk via Suppressing Modification of Human HDL

Nutrients ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1110 ◽  
Author(s):  
Jae-Yong Kim ◽  
Sang Hee Shim
Keyword(s):  
Kidney Diseases ◽  
Density Lipoprotein ◽  
Thiobarbituric Acid ◽  
Inhibitory Effect ◽  
Protective Role ◽  
Inhibitory Effects ◽  
Glycation End Products ◽  
Potent Inhibitory Effect ◽  
Key Factor

Atherosclerosis is the key factor responsible for cardiovascular events, which is a major cause of morbidities and mortalities worldwide. It is well known that high-density lipoprotein (HDL) oxidation and glycation increases the risk for atherosclerosis. Epimedium koreanum has been used as a traditional oriental medicine for treating erectile dysfunction, kidney diseases, osteoporosis, and breast cancer. However, no reports on the effects of E. koreanum on HDL modification exist. In this study, we investigated the inhibitory effects of E. koreanum extract and its eight flavonoids, which are: (1) anhydroicaritin 3-O-rhamnoside, (2) β-anhydroicaritin, (3–5) epimedins A-C, (6) epimedoside A, (7) icariin, and (8) des-O-methyl-β-anhydroicaritin, against HDL modification. HDLs obtained from pooled human plasma samples were incubated in vitro with E. koreanum extract or each compound in the presence of copper sulfate or fructose. The HDL modifications were evaluated by measuring generation of conjugated dienes, production of thiobarbituric acid reactive substances, change in electrophoretic mobility of apoA-I, advanced glycation end products formation, and apoA-I aggregation. Consequently, E. koreanum extract and compound 8 suppressed HDL modification through inhibition of lipid peroxidation, apoA-I aggregation, negative charge increase, and AGEs formation. In particular, compound 8 showed more potent inhibitory effect on HDL modification than the extracts, suggesting its protective role against atherosclerosis via inhibition of HDL oxidation and glycation.

scholarly journals Human macrophage-mediated oxidation of low-density lipoprotein is delayed and independent of superoxide production

1994 ◽  
Vol 301 (2) ◽  
pp. 421-428 ◽  
Author(s):  
B Garner ◽  
R T Dean ◽  
W Jessup
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Direct Methods ◽  
Thiobarbituric Acid ◽  
Human Monocyte ◽  
Ldl Oxidation ◽  
Human Macrophage ◽  
Low Density ◽  
Oxidatively Modified

There is growing evidence that oxidatively modified low-density lipoprotein (LDL) accumulates in the atherosclerotic intima of arteries. Cells present in the intima (including the monocyte/macrophage) are capable of oxidizing LDL in vitro, but the mechanisms by which this occurs are unknown. Several reports have claimed a crucial role for superoxide as a cell-derived radical species capable of enhancing the rate of LDL oxidation. We have used a sensitive h.p.l.c. system with chemiluminescence detection to measure LDL cholesteryl ester hydroperoxides at early stages of LDL oxidation. During the initial stages of LDL oxidation, there is at least a 2 h delay before human monocyte-derived macrophages enhance this process. Stimulation of these cells to produce large fluxes of superoxide does not increase the rate of LDL oxidation or decrease the delay of its onset. Prior exposure of LDL to a high flux of superoxide does not increase its susceptibility to oxidation by human monocyte-derived macrophages. We also show that the thiobarbituric acid-reactive substances (TBARS) assay does not always correlate with more direct methods of assessing LDL oxidation and confirm recent reports that superoxide dismutase only partially inhibits cell-mediated LDL oxidation. We conclude that superoxide does not play a major role in human monocyte-derived macrophage-mediated LDL oxidation under the conditions that we describe.

scholarly journals Effect of insulin on low-density-lipoprotein metabolism in human lymphocytes in vitro

1986 ◽  
Vol 233 (2) ◽  
pp. 565-570 ◽  
Author(s):  
S Suresh ◽  
V Warty ◽  
M Virji ◽  
A Sanghvi
Keyword(s):  
Cholesterol Synthesis ◽  
Human Peripheral Blood ◽  
Reductase Activity ◽  
Human Lymphocytes ◽  
Density Lipoprotein ◽  
Inhibitory Effect ◽  
Peripheral Blood Lymphocytes ◽  
Cell Surface Receptor ◽  
Low Density

The metabolism of low-density lipoproteins (LDL) in vitro in the presence of insulin was studied in freshly isolated human peripheral-blood lymphocytes. Insulin appeared to decrease the binding affinity of 125I-LDL to its cell-surface receptor, without any change in apparent Vmax or in the number of LDL receptors. As a consequence, the absolute amounts of 125I-LDL internalized and degraded were lower in the presence of insulin than in its abscence, although the fraction of internalized 125I-LDL degraded in either instance was quite similar. 3-Hydroxy-3-methylglutaryl-CoA reductase activity, and hence cholesterol synthesis, were stimulated by insulin. This effect of insulin was independent of the inhibitory effect of LDL on cholesterol synthesis. At the same time, acid cholesterol esterase and acyl-CoA: cholesterol O-acetyltransferase activities were lower in cells incubated with insulin than in controls. The net effect of these metabolic alterations seems to be that cells accumulate greater quantities of free and esterified cholesterol when treated with insulin.

scholarly journals Chemical Composition, In Vitro and In Silico Antioxidant Potential of Melissa officinalis subsp. officinalis Essential Oil

Antioxidants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1081
Author(s):  
Matilda Rădulescu ◽  
Călin Jianu ◽  
Alexandra Teodora Lukinich-Gruia ◽  
Marius Mioc ◽  
Alexandra Mioc ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Chemical Composition ◽  
Essential Oil ◽  
In Silico ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Inhibitory Effect ◽  
Melissa Officinalis ◽  
Β Carotene

The investigation aimed to study the in vitro and in silico antioxidant properties of Melissa officinalis subsp. officinalis essential oil (MOEO). The chemical composition of MOEO was determined using GC–MS analysis. Among 36 compounds identified in MOEO, the main were beta-cubebene (27.66%), beta-caryophyllene (27.41%), alpha-cadinene (4.72%), caryophyllene oxide (4.09%), and alpha-cadinol (4.07%), respectively. In vitro antioxidant properties of MOEO have been studied in 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging, and inhibition of β-carotene bleaching assays. The half-maximal inhibitory concentration (IC50) for the radical scavenging abilities of ABTS and DPPH were 1.225 ± 0.011 μg/mL and 14.015 ± 0.027 μg/mL, respectively, demonstrating good antioxidant activity. Moreover, MOEO exhibited a strong inhibitory effect (94.031 ± 0.082%) in the β-carotene bleaching assay by neutralizing hydroperoxides, responsible for the oxidation of highly unsaturated β-carotene. Furthermore, molecular docking showed that the MOEO components could exert an in vitro antioxidant activity through xanthine oxidoreductase inhibition. The most active structures are minor MOEO components (approximately 6%), among which the highest affinity for the target protein belongs to carvacrol.

scholarly journals Antioxidant and Chemopreventive Effect of Aliophen® Formulation Based on Malts and Hops

Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 29
Author(s):  
Idolo Tedesco ◽  
Carmela Spagnuolo ◽  
Stefania Bilotto ◽  
Angelo A. Izzo ◽  
Francesca Borrelli ◽  
...  
Keyword(s):  
Health Effects ◽  
Low Density Lipoprotein ◽  
Antioxidant Properties ◽  
Density Lipoprotein ◽  
Ldl Oxidation ◽  
Preneoplastic Lesions ◽  
Chemically Induced ◽  
Chemopreventive Effect ◽  
The One ◽  
Higher Doses

Experimental and clinical studies evidenced the health effects of moderate consumption of beer, mainly due to the presence of bioactive compounds, such as polyphenols, vitamins, or fibers. To exploit the potential beneficial effect on health and in disease prevention of these compounds, a new beverage based on barley malts and hops named Aliophen® has been designed, through a patented production process, with a high total polyphenolic amount compared to alcohol-free beer and similar to the one present in light and dark beers. In the present study, the antioxidant activity of Aliophen® against low-density lipoprotein (LDL) oxidation and its ability to protect erythrocytes from hemolysis have been characterized. Moreover, the chemopreventive effect of Aliophen® against colon cancer has been assessed, employing a mouse model of chemically induced carcinogenesis using azoxymethane (AOM). Data obtained showed that Aliophen at a low dose (3 mg/kg) inhibited the formation of preneoplastic lesions, polyps, and tumors. At higher doses (300 mg/kg) the protective effect was measured in the first phase of the onset of cancer. The antioxidant properties of Aliophen® were also observed in AOM-treated mice where it increased the serum antioxidant capacity. Based on the data presented, Aliophen® can exert promising health effects, including an anticancer capacity presumably associated with its antioxidant properties.

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