Sustained postprandial decrease in plasma levels of LDL cholesterol in patients with type-2 diabetes mellitus

The Role of Fasting LDL-C Levels in Their Non-fasting Reduction in Patients With Coronary Heart Disease

The level of low-density lipoprotein cholesterol (LDL-C) decreases to a certain extent after daily meals; however, the influencing factor of this phenomenon has not been fully elucidated. This study included 447 patients with coronary heart disease (CHD). Serum levels of blood lipid parameters at 0, 2, and 4 hours (h) after a daily breakfast were monitored in all subjects. The levels of total cholesterol (TC), LDL-C, high-density lipoprotein cholesterol (HDL-C) and non-HDL-C significantly decreased, while those of triglycerides (TG) and remnant cholesterol (RC) significantly increased from baseline to 4 h in both male and female patients (P < 0.05). Multiple linear regression analysis showed that fasting LDL-C level, the non-fasting change in RC level at 4 h and fasting TG level were significant predictors of the non-fasting change in LDL-C level at 4 h in patients with CHD, and fasting LDL-C level was the most significantly associated with the non-fasting change in LDL-C level. Patients with lower levels of fasting LDL-C had smaller non-fasting changes in LDL-C levels. When the fasting LDL-C level was <1.4 mmol/L, both absolute reduction and percent reduction in LDL-C level at 4 h were almost zero, which means that the non-fasting LDL-C level at 4 h was approximately equivalent to its fasting value (P < 0.05). This result indicated that the non-fasting changes in LDL-C levels were influenced by fasting LDL-C levels in patients with CHD. When the fasting LDL-C level was <1.4 mmol/L, the non-fasting LDL-C level could replace the fasting value to guide treatment.

Comparison of Metformin and Repaglinide Monotherapy in the Treatment of New-Onset Type 2 Diabetes Mellitus

Objectives We intend to investigate the feasibility of using repaglinide as initial therapy in patients with newly diagnosed type 2 diabetes mellitus naive to the oral anti-hyperglycemic agents by validating the effects of repaglinide on glycemic control (HbA1c) in comparison with metformin monotherapy. Methodology This parallel-controlled, randomized study was carried at the outpatient department of a tertiary care hospital. Two-hundred patients of both genders with newly diagnosed type 2 diabetes mellitus were included. After taking relevant history and physical examination, we drew venous blood samples of each patient and sent them to the institutional laboratory for analysis of fasting blood sugar (FBS) levels, HbA1c, and lipid profile. We divided the patients into two subgroups based on the lottery method. Group A was prescribed metformin, and group B was prescribed repaglinide, while the dosages were adjusted according to the blood sugar levels. All data were analyzed using SPSS Software 25.0 (SPSS Inc., Chicago, USA). We reported the data as means along with the standard error. Results All patients completed the study. There was a decline in fasting blood glucose levels after three months of therapy, both in the metformin (135 mg/dl ± 6 mg/dl versus 115 mg/dl ± 7 mg/dl, p < 0.01) and repaglinide groups (145 ± 6 mg/dl versus 122 ± 6 mg/dl, p < 0.01). Similarly, significant reductions in HbA1c were seen in both metformin (7.12 ± 0.15% versus 6.67 ± 0.06%, p < 0.01) and repaglinide treatment groups (7.83 ± 0.67% versus 6.81 ± 0.07%, p < 0.01). After three months of treatment, body mass index (BMI) was significantly decreased in the metformin group (26.87±1.1 kg/m² versus 25.11 ± 0.44 kg/m², p < 0.05). However, the patients in repaglinide group demonstrated a very slight decrease in BMI (27.11 ± 1.6 kg/m² versus 26.47 ± 0.40 kg/m²). On follow-up, we found a significant decrease in triglyceride levels in both groups (p < 0.01 and p < 0.05. respectively). We also found that only the patients in metformin group showed some improvements in total cholesterol and low-density lipoprotein (LDL) levels (p < 0.05). Conclusion Our study concluded that both metformin and repaglinide have similar anti-hyperglycemic effects. Repaglinide can be prescribed as an alternative drug to metformin in patients with new-onset diabetes mellitus.

Meal frequency differentially alters postprandial triacylglycerol and insulin concentrations in obese women

OBJECTIVE

The aim of this study was to compare postprandial lipemia, oxidative stress, antioxidant activity, and insulinemia between a three and six isocaloric high-carbohydrate meal frequency pattern in obese women.

DESIGN AND METHODS

In a counterbalanced order, eight obese women completed two, 12-h conditions in which they consumed 1,500 calories (14% protein, 21% fat, and 65% carbohydrate) either as three 500 calorie liquid meals every 4-h or six 250 calorie liquid meals every 2-h. Blood samples were taken every 30 min and analyzed for triacylglycerol (TAG), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, myeloperoxidase, paraoxonase-1 activity, and insulin.

RESULTS

The TAG incremental area under the curve (iAUC) during the three meal condition (321 ± 129 mg/dl · 12 h) was significantly lower (P = 0.04) compared with the six meal condition (481 ± 155 mg/dl · 12 h). The insulin iAUC during the three meal condition (5,549 ± 1,007 pmol/l · 12 h) was significantly higher (P = 0.05) compared with the six meal condition (4,230 ± 757 pmol/l(.) 12 h). Meal frequency had no influence on the other biochemical variables.

CONCLUSIONS

Collectively, a three and six isocaloric high-carbohydrate meal frequency pattern differentially alters postprandial TAG and insulin concentrations but has no effect on postprandial cholesterol, oxidative stress, or antioxidant activity in obese women.

Effects of blackcurrant-based juice on atherosclerosis-related biomarkers in cultured macrophages and in human subjects after consumption of a high-energy meal

Regular consumption of fruit and vegetables may be associated with decreased CVD risk. In the present study, we investigated the effects of blackcurrant (BC) juice, rich in polyphenols and ascorbic acid, on oxidative and inflammatory biomarkers in cultured macrophages in vitro and in human subjects with an atherosclerosis-prone phenotype (after consumption of a high-energy meal). In cultured macrophages (RAW264.7), BC treatment significantly inhibited lipopolysaccharide-induced inflammation as indicated by lower mRNA levels of TNF-α, IL-1β and inducible NO synthase (iNOS) and lower nuclear p65 levels indicating decreased NF-κB activity. iNOS protein levels were lower and haem oxygenase 1 levels higher in BC-treated cells when compared with untreated controls. Subjects given a high-energy meal had elevated serum glucose and insulin levels with no significant difference between the BC-based juice and placebo treatment groups. TAG following meal ingestion tended to be attenuated after the BC treatment. Plasma ascorbic acid and radical-scavenging capacity were decreased following placebo meal consumption; however, BC significantly elevated both parameters compared with baseline and placebo ingestion. Plasma oxidised LDL, α-tocopherol and paraoxonase activity were unchanged in both treatment groups. Furthermore, production of TNF-α and IL-1β was not significantly changed by BC meal consumption. The present results suggest potential antioxidative and anti-inflammatory properties of BC in vitro in cultured macrophages. Although the observations were not directly transferable to a postprandial in vivo situation, the present results show that BC juice consumption may improve postprandial antioxidant status as indicated by higher ascorbic acid levels and free radical-scavenging capacity in plasma.

Agreement Between Fasting and Postprandial LDL Cholesterol Measured with 3 Methods in Patients with Type 2 Diabetes Mellitus

BACKGROUND

LDL cholesterol (LDL-C) is a modifiable cardiovascular disease risk factor. We used 3 LDL-C methods to study the agreement between fasting and postprandial LDL-C in type 2 diabetes (T2DM) patients.

METHODS

We served 74 T2DM patients a standardized meal and sampled blood at fasting and 1.5, 3.0, 4.5, and 6.0 h postprandially. We measured LDL-C by use of modified β quantification (MBQ), the Friedewald equation (FE), and a direct homogeneous assay (DA). We evaluated agreement using 95% limits of agreement (LOA) within ±0.20 mmol/L (±7.7 mg/dL).

RESULTS

LDL-C concentrations at all postprandial times disagreed with those at fasting for all methods. In 66 patients who had complete measurements with all LDL-C methods, maximum mean differences (95% LOA) in postprandial vs fasting LDL-C were −0.16 mmol/L (−0.51; 0.19) [−6.2 mg/dL (−19.7; 7.3)] with MBQ at 3 h; −0.36 mmol/L (−0.89; 0.17) [−13.9 mg/dL (−34; 6.6)] with FE at 4.5 h; and −0.24 mmol/L (−0.62; 0.05) [−9.3 mg/dL (−24; 1.9)] with DA at 6.0 h. In postprandial samples, FE misclassified 38% of patients (two-thirds of statin users) into lower Adult Treatment Panel III (ATP III) risk categories. Greater disagreement between fasting and postprandial LDL-C was observed in individuals with postprandial triglyceride concentrations &gt;2.08 mmol/L (&gt;184 mg/dL) and in women (interactions: P ≤ 0.038).

CONCLUSIONS

Differences up to 0.89 mmol/L (34 mg/dL) between fasting and postprandial LDL-C concentrations, with postprandial LDL-C concentrations usually being lower, were found in T2DM by 3 different LDL-C methods. Such differences are potentially relevant clinically and suggest that, irrespective of measurement method, postprandial LDL-C concentrations should not be used to assess cardiovascular disease risk.

Non-HDL cholesterol shows improved accuracy for cardiovascular risk score classification compared to direct or calculated LDL cholesterol in a dyslipidemic population

BACKGROUND

Our objective was to evaluate the accuracy of cardiovascular disease (CVD) risk score classification by direct LDL cholesterol (dLDL-C), calculated LDL cholesterol (cLDL-C), and non-HDL cholesterol (non-HDL-C) compared to classification by reference measurement procedures (RMPs) performed at the CDC.

METHODS

We examined 175 individuals, including 138 with CVD or conditions that may affect LDL-C measurement. dLDL-C measurements were performed using Denka, Kyowa, Sekisui, Serotec, Sysmex, UMA, and Wako reagents. cLDL-C was calculated by the Friedewald equation, using each manufacturer's direct HDL-C assay measurements, and total cholesterol and triglyceride measurements by Roche and Siemens (Advia) assays, respectively.

RESULTS

For participants with triglycerides<2.26 mmol/L (<200 mg/dL), the overall misclassification rate for the CVD risk score ranged from 5% to 17% for cLDL-C methods and 8% to 26% for dLDL-C methods when compared to the RMP. Only Wako dLDL-C had fewer misclassifications than its corresponding cLDL-C method (8% vs 17%; P<0.05). Non-HDL-C assays misclassified fewer patients than dLDL-C for 4 of 8 methods (P<0.05). For participants with triglycerides≥2.26 mmol/L (≥200 mg/dL) and<4.52 mmol/L (<400 mg/dL), dLDL-C methods, in general, performed better than cLDL-C methods, and non-HDL-C methods showed better correspondence to the RMP for CVD risk score than either dLDL-C or cLDL-C methods.

CONCLUSIONS

Except for hypertriglyceridemic individuals, 7 of 8 dLDL-C methods failed to show improved CVD risk score classification over the corresponding cLDL-C methods. Non-HDL-C showed overall the best concordance with the RMP for CVD risk score classification of both normal and hypertriglyceridemic individuals.