Potent inhibitors of glucagon-stimulated adenylate cyclase associated with serum lipoprotein particles

1989 ◽  
Vol 67 (11-12) ◽  
pp. 759-762
Author(s):  
Philip J. Bilan ◽  
Jonathan B. Weitzman ◽  
Tracey Pflieger ◽  
C. Roy D. Lancaster ◽  
Alan Stafford ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Adenylate Cyclase ◽  
Serum Lipoprotein ◽  
Normal Phase ◽  
Acetone Extract ◽  
High Density Lipoproteins ◽  
Low Density ◽  
Inhibitory Effects ◽  
Acetone Extraction ◽  
Layer Chromatography

Lipoprotein fractions from some individuals have inhibitory effects on rat liver adenylate cyclase. Precipitation of the lipoprotein fractions with acetone released an inhibitory factor, which was soluble in acetone–H2O (3:1, v/v). The inhibition was greater against glucagon-stimulated activity than against basal activity. Acetone extraction increased the potency of inhibition. All three lipoprotein fractions, i.e., very low, low, and high density lipoproteins, released some inhibitory component after acetone extraction. The inhibitor was concentrated in the lipoprotein fractions, since acetone extraction of plasma did not release an inhibitor. The acetone extract from the very low density liproprotein was the most inhibitory. This material was further purified and partially characterized. The inhibitor had a molecular mass of about 500. It was inhibitory at micromolar concentrations. The material was sufficiently hydrophobic to migrate in normal-phase thin-layer chromatography (TLC). Nuclear magnetic resonance results indicated that it was not a polar lipid. There were several different inhibitory factors that were separable by TLC. The sequestration of these inhibitors into lipoproteins reduced their effectiveness in inhibiting the action of counter-regulatory hormones, such as glucagon.Key words: glucagon, adenylate cyclase, lipoprotein, diabetes mellitus.

scholarly journals Extraction, isolation and characterization of depsidones from Usnea baileyi (Stirt.) Zahlbr collected from tree barks in Tam Bo Mountain of Di Linh, Lam Dong Province, Viet Nam

2018 ◽  
Vol 21 (1) ◽  
pp. 24-31
Author(s):  
Kieu Van Nguyen ◽  
Huy Thuc Duong
Keyword(s):  
Spectroscopic Analysis ◽  
Normal Phase ◽  
Acetone Extract ◽  
Viet Nam ◽  
Current Investigation ◽  
Chemical Structures ◽  
Isolation And Characterization ◽  
Tree Barks ◽  
Layer Chromatography

Chemical data on the lichen Usnea baileyi are scarce. The current investigation reports the extraction, isolation and characterization of depsidones from this lichen collected in Lam Dong Province. Eight depsidones were isolated and elucidated, including methylstictic acid (1), stictic acid (2), cryptostictic acid (3), 8’-O-methylmenegazziaic acid (4), menegazziaic acid (5), 8’- O-methylconstictic acid (6), constictic acid (7), and hypoconstictic acid (8). Multi chromatographic methods comprising normal phase silica gel column chromatography and thin layer chromatography were applied to the crude acetone extract to isolate and purify compounds 1-8. Their chemical structures were elucidated by spectroscopic analysis as well as comparing their data with ones in the literature.

scholarly journals Metabolic effects of nettle extract in diabetes mellitus

2011 ◽  
Vol 10 (5) ◽  
pp. 116-120
Author(s):  
T. V. Yakimova ◽  
O. N. Nasanova ◽  
M. V. Meleshko ◽  
V. N. Burkova
Keyword(s):  
Diabetes Mellitus ◽  
High Fat Diet ◽  
Glycosylated Hemoglobin ◽  
Atherogenic Index ◽  
Metabolic Effects ◽  
High Density Lipoproteins ◽  
Low Density ◽  
High Fat ◽  
Experimental Diabetes Mellitus ◽  
Diabetes Mellitus Type Ii

The blood level of glucose, glycosylated hemoglobin, triglycerides, total cholesterol, summary content of very low density and low density lipoproteins, high density lipoproteins glycosylation's degree had been decreased with the nettle (Urtica dioica) extract in experimental diabetes mellitus type II in rats that was being caused with streptozotocine intraperitoneal injection and high-fat diet. The effect did not depend on food regimen during the therapy. The cholesterol atherogenic index has been decreased and the sensitivity to insulin has been recovered with the nettle extract when high-fat diet only. The level of blood glucose and glycosylated hemoglobin has been decreased with metformin when usual food regimen during the therapy. The lipid content and cholesterol atherogenic index has been normalized with metformin when both variant of diet.

scholarly journals Atherogenicity of blood plasma lipid spectrum during sugar-reducing therapy in patients with noninsulin-dependent diabetes mellitus

1995 ◽  
Vol 41 (3) ◽  
pp. 13-16
Author(s):  
A. S. Ametov ◽  
N. V. Perova ◽  
N. L. Vinnitskaya ◽  
V. Z. Topchiashvili
Keyword(s):  
Diabetes Mellitus ◽  
Insulin Resistance ◽  
Insulin Therapy ◽  
Blood Plasma ◽  
Plasma Lipid ◽  
High Density Lipoproteins ◽  
Dependent Diabetes Mellitus ◽  
Low Density ◽  
Secondary Failure ◽  
Lipid Spectrum

Blood plasma lipoprotein spectrum and phospholipid spectrum of high density lipoproteins (HDLP) was studied in patients with newly detected noninsulin-dependent diabetes mellitus (NIDDM) and in patients with "secondary failure" of sulfanilamide drugs. Hyperlipidemia, mainly at the expense of increased concentration of triglycerides, very low density lipoproteins, total cholesterol, and low density lipoprotein cholesterol, was detected in the patients. HDLP phospholipid composition was disturbed, with sphyngomyelin level increased and lecithin content decreased. Glurenorm therapy led to reduction of the atherogenicity of blood plasma lipid spectrum despite the persistent basal and postload hyperinsulinemia, thus indirectly indicating an improved function of endogenous insulin. Antiatherogenic effect of glurenorm is evidently mediated by reduction of insulin resistance due to extrapancreatic effect of the drug. Intensive insulin therapy of patients with secondary failure led to a marked reduction of atherogenic components of lipid spectrum. The hypolipidemic effect of insulin therapy seems to be due to recovery of the inhibitory effect of insulin on lipolysis against the background of improved sensitivity to insulin and reduced insulin resistance. A positive effect of insulin therapy on lipid metabolism should not be regarded as an evidence in favor of theoretical assumptions and apprehensions about increased risk of atherogenesis as a result of exogenous hyperinsulinemia.

scholarly journals Study the Effects of Polyphenolic Cocoa beans Extracts (CE) in Streptozotocin-induced diabetic mice.

2010 ◽  
Vol 7 (1) ◽  
pp. 721-726
Author(s):  
Baghdad Science Journal
Keyword(s):  
Diabetes Mellitus ◽  
Metabolic Diseases ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
High Density ◽  
High Density Lipoproteins ◽  
Low Density ◽  
Diabetic Mice ◽  
Cocoa Beans ◽  
Once Daily

Diabetes Mellitus is a group of metabolic diseases characterized by increasing of glucose level in plasma compared with normal value (hyperglycemia). This disease also causes elevation of lipid profile levels except HDL (High density lipoproteins) which increased relatively. The effects of the polyphenolic mixture (catechins, epicatechins, procyanidin B1, procyanidin B2 and procyanidin C1) on total cholesterol (TC), triacylglycerol (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) were studied in (30) streptozotocin-induced diabetic mice with (20-25)gm weight. Mice were given (30 mg/mL) of Polyphenolic Cocoa beans Extracts (CE) once daily for (7) days before Streptozotocin STZ injection and for (21 day) there after. At (day7) (TC), (TG) and (LDL) levels were elevated (P

scholarly journals Efeito da redução de peso em pacientes submetidos à técnica do Bypass Gástrico em Y-de-Roux

2019 ◽  
Vol 28 (1) ◽  
pp. 11
Author(s):  
Midia Alves Farias de Melo ◽  
Tatiane Dos Santos ◽  
Luiny Godoy ◽  
Ketlen Silva ◽  
Thais Regina Mezzomo ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Low Density Lipoproteins ◽  
High Density ◽  
High Density Lipoproteins ◽  
Low Density

ObjetivoIdentificar o impacto da cirurgia bariátrica sobre o perfil metabólico de indivíduos submetidos ao Bypass Gástrico em Y-de Roux. MétodosAnálise retrospectiva do período pré- e pós-operatório de cinquenta e três pacientes submetidos à técnica cirúrgica Bypass Gástrico em Y-de-Roux, com idade entre 18 e 63 anos, atendidos em um Centro de Saúde Preventiva do Município de Curitiba, Paraná. Foram coletados dados antropométricos e laboratoriais de Low Density Lipoproteins, High Density Lipoproteins, triglicérides, glicose de jejum e insulina de jejum no período pré- e pós-operatório (6 meses, 12 meses e 24 meses) de prontuários médicos. ResultadosEntre os pacientes, 94,34% (n=50) eram mulheres com idade média de 45,04±9,17 anos. Foi observada redução significativa do peso e índice de massa corporal, assim como concentrações inferiores de glicose sérica. O colesterol total (192,19±38,66 vs 162,38±30,42, p=<0,05), low density lipoproteins (119,81±31,68 vs 95,10±22,77), e Triglicérides (153,11±84,10 vs 80,64±35,52, p<0,01) quando comparados os períodos pré-operatório e pós-operatório (24 meses). No pós-operatório de 24 meses foi observada remissão da hipertensão arterial, diabetes Mellitus e dislipidemia, sendo a obesidade mais comum no pós-operatório de 2 anos estando presente em 21,00% dos pacientes. ConclusãoO Bypass Gástrico em Y-de-Roux mostrou ser um procedimento eficaz na melhora do perfil metabólico de indivíduos com obesidade mórbida, com resultados consistentes na perda de peso e remissão das principais comorbidades associadas à obesidade.

scholarly journals Human plasma phospholipid transfer protein accelerates exchange/transfer of α-tocopherol between lipoproteins and cells

1995 ◽  
Vol 305 (2) ◽  
pp. 659-667 ◽  
Author(s):  
G M Kostner ◽  
K Oettl ◽  
M Jauhiainen ◽  
C Ehnholm ◽  
H Esterbauer ◽  
...  
Keyword(s):  
Serum Lipoprotein ◽  
Alpha Tocopherol ◽  
Plasma Lipoproteins ◽  
High Density Lipoproteins ◽  
Phospholipid Transfer Protein ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Transfer Protein ◽  
Transfer Processes ◽  
Phospholipid Transfer

alpha-Tocopherol (alpha-T), an important anti-oxidant of plasma lipoproteins and cell membranes, is secreted from liver together with very-low-density lipoproteins into the blood stream. Other serum lipoprotein classes gain alpha-T by exchange and transfer processes. We show here that the lipoprotein-free d > 1.22 g/ml fraction of human or pig serum increases the exchange rate of alpha-T by a factor of 2-4 as compared with spontaneous exchange/transfer. The alpha-T exchange/transfer (alpha-TET) activity was purified by multiple-step column chromatography. It gave a single band in PAGE with an apparent molecular mass of 75 kDa, and was found to be identical with the phospholipid transfer protein (PLTP). PLTP catalysed alpha-T exchange between different lipoprotein classes, as well as the transfer of alpha-T from artificial liposomes to high-density lipoproteins. The alpha-TET activity measured with a newly developed assay in ten healthy people was 2.45 +/- 0.88 nmol.ml-1.h-1.alpha-TET activity was negatively correlated with plasma low-density lipoprotein-cholesterol (r = -0.75; P < 0.01). It is concluded that human PLTP catalyses exchange/transfer processes of alpha-T between lipid compartments. This factor may be of relevance in atherogenesis and tumour initiation and growth.

Simple Method for Quantifying Alpha-Tocopherol in Low-Density+Very-Low-Density Lipoproteins and in High-Density Lipoproteins

1992 ◽  
Vol 38 (9) ◽  
pp. 1792-1795 ◽  
Author(s):  
G Carcelain ◽  
F David ◽  
S Lepage ◽  
D Bonnefont-Rousselot ◽  
J Delattre ◽  
...  
Keyword(s):  
High Performance ◽  
Reversed Phase ◽  
Serum Lipoprotein ◽  
High Density ◽  
Alpha Tocopherol ◽  
High Density Lipoproteins ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Simple Method ◽  
Selective Precipitation

Abstract We assessed the distribution of alpha-tocopherol in serum lipoprotein samples after separating the lipoprotein fractions by either sequential ultracentrifugation or selective precipitation with sodium phosphotungstate-magnesium chloride reagent. alpha-Tocopherol concentrations were determined by reversed-phase high-performance liquid chromatography. After ultracentrifugation, we found that in men, low- and very-low-density serum lipoproteins (LDL-VLDL) contained 53.6% of alpha-tocopherol vs 46.4% in high-density lipoproteins (HDL). In women, serum LDL-VLDL contained 45.6% alpha-tocopherol after ultracentrifugation vs 54.4% in HDL. After selective precipitation, the proportions of alpha-tocopherol in men were 56.1% in LDL-VLDL vs 43.9% in HDL, and in women, 45.4% in LDL-VLDL vs 54.6% in HDL. After selective precipitation, alpha-tocopherol recovery from whole lipoprotein fractions was 97% to 100% vs 80% after ultracentrifugation, thus allowing more accurate alpha-tocopherol quantification than after separation by ultracentrifugation.

scholarly journals Effect of serum lipoproteins on the adenylate cyclase activity of rat liver plasma membranes

1981 ◽  
Vol 196 (3) ◽  
pp. 899-902 ◽  
Author(s):  
G Ghiselli ◽  
C R Sirtori ◽  
S Nicosia
Keyword(s):  
Adenylate Cyclase ◽  
Rat Liver ◽  
Plasma Membranes ◽  
High Density Lipoproteins ◽  
Low Density ◽  
Serum Lipoproteins ◽  
Maximal Increase ◽  
Liver Plasma Membranes ◽  
Rat Liver Plasma Membranes ◽  
Active Class

Four rat lipoprotein classes [lymph chylomicrons, VLD (very-low-density), LD (low-density) and HD (high-density) lipoproteins] were tested for their ability to affect basal adenylate cyclase (EC 4.6.1.1) activity of rat liver plasma membranes. All the lipoproteins, with the exception of lymph chylomicrons, effectively increase the enzyme activity. VLD lipoproteins are the most active class (67% maximal increase), followed by HD lipoproteins (33%) and LD lipoproteins (23%). The effect of VLD lipoproteins is additive to that elicited by GTP or GTP plus glucagon (at least within a certain concentration range). VLD lipoproteins affect only the Vmax. of the enzyme, not the Km.

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