Determination Of Plasma Triglycerides Research Articles

Glucose added to a fat load suppresses the postprandial triglyceridemia response in carriers of the -1131C and 56G variants of the APOA5 gene.

Apolipoprotein A-V plays an important role in the determination of plasma triglyceride (TG) concentration. We aimed to determine whether polymorphisms -1131T>C (rs662799) and 56C>G (rs3135506) of the APOA5 gene have an impact on the course of postprandial lipemia induced by a fat load and a fat load with added glucose. Thirty healthy male volunteers, seven heterozygous for the -1131C variant and three for the 56G variant (HT) carriers, and 20 wild-type (WT) carriers underwent two 8-hour tests of postprandial lipemia - one after an experimental breakfast consisting of 75 g of fat and second after a breakfast consisting of 75 g of fat and 25 g of glucose. HT carriers had a higher postprandial response after fat load than WT carriers (AUC TG: 14.01+/-4.27 vs. 9.84+/-3.32 mmol*h/l, respectively, p=0.016). Glucose added to the test meal suppressed such a difference. Heterozygous carriers of the variants of APOA5 (-1131C and 56G) display more pronounced postprandial lipemia after pure fat load than WT carriers. This statistically significant difference disappears when glucose is added to a fat load, suggesting that meal composition modulates the effect of these polymorphisms on the magnitude of postprandial lipemia.

Plasma triglyceride determination can identify increased risk of statin-induced type 2 diabetes: A hypothesis

ObjectiveTo evaluate the ability of plasma triglyceride (TG) measurements to identify statin-treated persons at accentuated risk of statin-induced type 2 diabetes (T2DM). MethodsThe experimental population consisted of nondiabetic, statin-treated patients (n = 469), classified as being at high risk for T2DM, subdivided on the basis of a plasma TG concentration of 1.7 mmol/L. Comparisons were made of demographic characteristics, concentrations of fasting glucose, insulin, HbA1c, and hs-CRP, oral glucose tolerance tests, estimates of insulin action and secretion, and lipid/lipoprotein profiles. ResultsDespite similar fasting glucose and HbA1c concentrations, patients with elevated TG concentrations displayed markers of increased risk of T2DM (insulin resistance and compensatory hyperinsulinemia), more adverse lipid/lipoprotein profiles, and increased prevalence of abnormal hs-CRP values. ConclusionThese findings demonstrate that plasma TG concentrations ≥ 1.7 mmol/L identified a subset of individuals at enhanced risk of developing statin-induced diabetes within a population classified prior to statin treatment as being at high risk of T2DM.

The association between APOA5 haplotypes and plasma lipids is not modified by energy or fat intake: The Czech HAPIEE study

Background and aimsSeveral smaller studies reported interactions between dietary factors and apolipoprotein A5 (APOA5) gene polymorphisms in determination of plasma lipids. We tested interactions between APOA5 haplotypes and dietary intake in determination of plasma triglycerides (TG) and other lipids. Methods and resultsParticipants (5487 males and females aged 45–69) were classified according to the number (0, 1, 2+) of minor APOA5 alleles (using T-1131 > C; rs662799 and Ser19 > Trp; rs3135506 polymorphisms) and into three groups of low (bottom 25%), medium (26th–75th percentile) and high (top 25%) of intake of total energy and total, saturated and polyunsaturated fats, assessed by food frequency questionnaire. The age-sex adjusted geometric means of plasma TG increased with the number of minor alleles, from 1.57 (standard error 0.01), to 1.79 (0.02) to 2.29 (0.10) mmol/L (p < 0.00001) but TG did not differ between groups with low, medium and high total energy intake (p = 0.251). TG concentrations were highest in subjects with the combination of 2+ minor alleles and the highest energy intake (mean 2.59 [0.19], compared with 1.62 [0.03] in subjects with lowest energy intake and no minor allele) but the interaction between energy intake and APOA5 haplotypes was not statistically significant (p = 0.186). Analogous analyses with total, saturated and polyunsaturated fat intake yielded similar nonsignificant results. Effects of APOA5 and dietary intakes on total and HDL cholesterol were weaker and no interactions were significant. ConclusionIn this Slavic Caucasian population sample, we did not detect the hypothesized interaction between common SNPs within the APOA5 gene and diet in determination of blood lipids.

The effect of guar meal (germ fraction) and β-mannanase enzyme on growth performance and plasma lipids in broiler chickens

A completely randomized design experiment was conducted to assess the effect of β-mannanase enzyme on a commercial broiler chickens strain fed with different levels of guar meal germ fraction (GM) Each treatment was assigned to 4 replicate for a total of 24 pens, consisting of 15 chicks per pen, in randomized complete block design. Experimental groups include: control diet without GM, low level of GM (2, 4 and 6% in starter, grower and finisher diets respectively), intermediate level of GM (4, 6 and 8% in starter, grower and finisher diets respectively), intermediate GM+β-mannanase enzyme, high levels of GM (6, 9 and 12% in starter, grower and finisher diets respectively) and high GM+β-mannanase enzyme. Body weight gain (BWG), feed intake (FI) and feed:gain ratio (F:G) were measured weekly. At the end of the experiment (42 day of age), blood samples were collected for the determination of plasma triglycerides, totalcholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL) and then the chicks were killed for carcass dressing. BWG, FI, F:G ratio and plasma lipids were affected by experimental groups (P 0.05). In the control, low GM and intermediate GM+β-mannanase groups, BWG, FI, F:G ratio, relative weight of carcass and giblets and plasma lipids were better than other treatments. High GM in broilers diet deleteriously affected growth performance, FI, F:G ratio and plasma lipids. Result indicates that optimal levels of guar meal are low level without β-mannanase and intermediate level with β-mannanase without adverse effects on growth performance or plasma lipids of broiler chickens. Keywords: Guar meal, β-mananase, plasma lipid, performance, broiler chicken

APOA5 polymorphisms influence plasma triglycerides in young, healthy African Americans and whites of the CARDIA Study

Genetic variation in the apolipoprotein A-V gene (APOA5) has been associated with variation in plasma triglyceride (TG) levels in African American and white females and males older than 40 years and/or at increased risk of coronary artery disease. We have examined whether plasma TG levels are associated with 16 APOA5 polymorphisms in young (18-30 years) African American (1,075 females and 783 males) and white (1,041 females and 932 males) individuals of the Coronary Artery Risk Development in Young Adults (CARDIA) Study selected without regard to health. Plasma TG was significantly (P < 0.01) associated with markers 27376 and 28837 (-3A/G) in both white females and males, with 27709 (-1131T/C) and 29085 in white males, with 29009 (S19W) in African American females and white males, and with 30966 in African American females. No statistically significant associations were observed in African American males. These six single-nucleotide polymorphisms individually accounted for 0-0.78% of lnTG variation among white females, 0-2.46% among white males, and 0-0.69% among African American females. The results of our study suggest a small but replicable context-dependent influence of the APOA5 gene region on plasma TG levels in young, healthy individuals.

Genetic analysis of APOAV polymorphisms (T-1131/C, Ser19/Trp and Val153/Met): no effect on plasma remnant particles concentrations

Background: APOAV is newly described protein, which plays a crucial role in the determination of plasma triglyceride (TG) levels. Remnant lipoproteins (RLPs) result from partial catabolised TG-rich particles. Elevated levels of RLP are associated with atherosclerosis, and they are a predictor of coronary events in patients with coronary artery disease. Methods: We have evaluated the influence of APOAV polymorphisms (T-1131/C, Ser19/Trp and Val153/Met were measured by PCR and restriction analysis) on plasma levels of RLP-cholesterol and RLP-TG in 285 unrelated representative selected individuals (131 men and 154 women) aged 33–72 years. Results: RLP-cholesterol and RLP-TG levels were not significantly influenced by the APOAV variants either in whole population or in males and females, if analyzed separately. Conclusions: We conclude that variations T-1131/C, Ser19/Trp and Val153/Met in the APOAV gene have no effect on plasma levels of remnant particles.

New variants in the apolipoprotein AV gene in individuals with extreme triglyceride levels.

Animal studies (on transgenic and knock-out mice) and human association analysis assessed the importance of APOAV gene for plasma triglyceride determination. New APOAV missense variants (Val153 --> Met and Cys185 --> Gly) have been detected recently. We have analyzed these variants in 83 unrelated patients with extreme lipid parameters (triglycerides of 20.4+/-2.8 mmol/l and total cholesterol of 10.4+/-3.7 mmol/l) and in a control population group consisting of 2,559 unrelated Caucasians. In patients, the frequency of the Met153 carriers was slightly but not significantly higher (9.64 % vs. 6.49 %) compared to the population sample. This suggested that Val153 Met polymorphism in the APOAV gene does not represent an important risk factor for developing the extreme levels of plasma triglycerides. We did not detect carriers of the Gly185 allele among patients or 420 healthy individuals. We suppose that this variant is probably not present in Caucasian populations

Contribution of APOA5 gene variants to plasma triglyceride determination and to the response to both fat and glucose tolerance challenges

The aim of this study was to investigate the influence of APOA5 variants on fasting lipids and to the response to both an oral fat tolerance test (OFTT) and an oral glucose tolerance test (OGTT). The association of two APOA5 SNPs [S19W (SNP5), −1131T>C (SNP3)] and an APOA4/A5 intergenic SNP [−12238T>C (SNP4)] were examined in healthy young men ( n=774) who had undergone both an OFTT and an OGTT. Both −1131T>C and S19W rare alleles were associated with triglyceride (TG)-raising effects (11%, P=0.008; 21% (in cases), P<0.026, respectively) and showed additive effects on TG. None of the variants influenced the responsiveness to the OFTT after correcting for baseline TG. Homozygosity for the −12238T>C rare allele was associated with higher waist to hip ratio ( P<0.0006), systolic blood pressure ( P=0.012) and AUC and peak of insulin after OGTT ( P=0.003 and P=0.027, respectively), traits that define the metabolic syndrome. Our results strongly support the role of APOA5 in determining plasma TG levels in an age-independent manner and highlight the importance of the APOC3/A4/A5 gene cluster in both TG and metabolic homeostasis.

High-performance liquid chromatographic determination of plasma triglyceride type composition in a normal population of Barcelona: Relationship with age, sex and other plasma lipid parameters

A coupled TLC−HPLC procedure is proposed for the separation and determination of plasma triglycerides. The method was tested by application to plasma samples corresponding to a normal population of Barcelona (Spain). Eighteen different triglyceride types were identified and their relative proportions were established, in order to give a “normal profile” for men and women. Sex-related differences ( p < 0.05) were only found for dioleostearin and palmitodilinolein + linoleooleopalmitolein (LLP + LOPa). A correlation study showed that palmitodiolein and total cholesterol levels increase with age, whereas LLP−LOPa decreases in men and palmitolinoleoolein + palmitooleopalmitolein in women.

Fully enzymic method of plasma triglyceride determination using an immobilized glycerol dehydrogenase nylon-tube reactor

A new, enzymic method of triglyceride determination in serum and plasma by use of an immobilized glycerol dehydrogenase nylon-tube reactor, integrated into the flow system of an AutoAnalyzer II (Technicon) is described. The combination of this reactor, stable for 1500–2000 tests, with the lipolytic enzymes which are added in solution yields a reliable and reproducible assay, which correlates well with the commonly used fully enzymic triglyceride determination. Using this new method, the cost can be reduced to about one-third of that of the other method.

Interference of an anesthetic preparation with plasma triglyceride determinations.

A marked elevation in plasma triglycerides is observed when experimental animals are anesthetized with a pentobarbital sodium injection (Nembutal), a most widely used anesthetic in animal experiments. This is proven, however, to be a false rise due to the interference of propylene glycol present in the solvent of the injection with the plasma triglyceride determinations. One mole of propylene glycol produces one mole of formaldehyde by oxidation. The formaldehyde thus generated from propylene glycol mixes with those from glycerol moiety of plasma triglycerides, and gives an enhanced color reaction to all chromogenic reactions with formaldehyde. Since most of the chemical methods for plasma triglyceride determination is based on either one of these color reactions, we have to pay attention to a hypertriglyceridemia due to such influence as exerted by a solvent additive of propylene glycol upon the triglyceride measurements.

Use of 3-Methyl-2-Benzothiazolone Hydrazone in an Automated Colorimetric Method for Determination of Triglycerides in Plasma or Serum

Abstract A new automated colorimetric method is described for the determination of serum or plasma triglycerides. The samples are extracted with 2-propanol containing activated alumina. An AutoAnalyzer Sampler II and Proportioning Pump II are used in combination with a Gilford Model 300 N spectrophotometer and Model 3091-A debubbler flow cell. Following on-line saponification, glycerol is oxidatively cleaved with sodium metaperiodate. The resulting formaldehyde is reacted with 3-methyl-2-benzothiazolone hydrazone (MBTH) under mild conditions to produce the corresponding azine. Further reaction of MBTH with the azine in the presence of an oxidizing agent results in the formation of a blue cationic adduct. Beer's law is obeyed, at 670 nm, to a triglyceride concentration of 400 mg/100 ml. Because of the high sensitivity of the MBTH reaction, short incubation periods, high sampling rates (60/h), and low flow rates can be used. The results correlate well with those obtained by the Kessler-Lederer method and by a totally enzymatic method.

Improved Accuracy in Automated Fluorometric Determination of Plasma Triglycerides

Abstract Accuracy of the automated fluorometric measurement of triglyceride by the technique of Kessler and Lederer is limited by the instability of the baseline. Concentration of the alcoholic KOH reagent was modified, and the pump tube manifold altered to provide on-stream mixing of the KOH reagent, which overcame this difficulty. A relatively inexpensive fluorometer with the solid-state photomultiplier microphotometer, modified to provide dual-scale sensitivity, was used to increase precision of measurements. Analytical results for 30 serum samples, taken from three pools of frozen serum, show the accuracy of the measurements to be ±8 mg/100 ml and the standard deviation ±9 mg/100 ml for a single determination.

Erratum

Abstract The article "The Determination of Triglycerides in Plasma and Tissues" by Vishwanath M. Sardesai and Joan A. Manning—Clin.. (Chem. 14, 156 (1968)—contains three errors. On p. 157 under Materials: Reagent 3 should read Alcoholic potassium hydroxide ... with 95% ethyl alcohol. Working solution: dilute 100 ml of stock solution to 50 ml with 95% alcohol on day of use. On p. 157 under Materials: Reagent 6 should read Sodium arsenite, 0.5 M. On p. 158, line 9: ... glycerol released on saponification). After exactly 10 min., the oxidation was stopped by the addition of 0.1 ml sodium arsenite. Several minutes later....

Erratum

Abstract The article "The Determination of Triglycerides in Plasma and Tissues" by Vishwanath M. Sardesai and Joan A. Manning—Clin. Chem.13, 326 (1968)—contaitis three errors. Under Reagents, p. 157: To "3. Alcoholic potassiImmll hydroxide . . . 95% alcohol." should be added "For working solution, dilute 10 ml. of this stock solution to 50 ml. with 95% alcohol on day of use." Under Reagents, p. 157: Reagent 6 should read "Sodium arsenite, 0.5 M." Under Methods, p. 158, the sentence starting oii line 9 should read "After exactly 10 min. the oxidation was stopped by the addition of 0.1 ml. sodium arsenite."

The Determination of Triglycerides in Plasma and Tissues

Abstract A simple method for the determination of plasma and tissue triglycerides is described. This procedure involves the extraction and saponification of triglycerides, the oxidation of the glycerol moiety to formaldehyde, and the conversion of formaldehyde to a yellow-colored compound, 3,5 diacetyl-1-4 dihydrolulidine, the intensity of which is determined spectrophotometrically. The recoveries of triglycerides added to plasma and tissues have been satisfactory. Plasma samples obtained from normal human subjects are found to have triglycerides in the range 83-200 mg./100 ml. From the standpoint of sensitivity, simplicity, and time required, this technic is believed to be an improvement over previously described procedures for triglyceride determination.

Direct determination of plasma triglyceride in decompensated diabetes in dogs

Summary Moderate insulin deficiency caused in diabetic dogs a highly significant increase ( P ≪0.001) in the plasma triglyceride (determined by a direct method), whereas the slight increase found in the plasma cholesterol was not significant ( P >0.05). On the basis of this result and findings reported in the literature, it is suggested that application of plasma triglyceride analysis may be valuable in some studies of lipid metabolism and its relation to atherosclerosis.

Further control and improvement of a method for determination of plasma triglyceride

Further control and improvement of a method for determination of plasma triglyceride

Further control and improvement of a method for determination of plasma triglyceride

Further control and improvement of a method for determination of plasma triglyceride

A Specific and Reasonably Accurate Method for Routine Determination of Plasma Triglyceride

A Specific and Reasonably Accurate Method for Routine Determination of Plasma Triglyceride