Glucose tolerance and lipid-lipoprotein levels in middle-aged powerlifters

Summary. The purpose of this study was to obtain information regarding the effects of a form of strength training (powerlifting) on certain coronary artery disease (CAD) risk factors in middle-aged men. The risk factors studied were the plasma lipid-lipoprotein profile, glucose tolerance and plasma insulin levels, all of which have been shown to be favourably influenced by endurance training in middle-aged and older men. Five elite powerlifters (52±9 years) were compared to distance runners and sedentary controls of similar age with whom they were matched in terms of body fatness as estimated from skinfold thickness measurements. The powerlifters had a significantly (P < 0·01) lower HDL cholesterol (HDL-C) level (34±4 mg/100 ml) than the sedentary controls (48±12 mg/100 ml) and runners (54±8 mg/100 ml). The total cholesterol to HDL-C ratio, a good indicator of CAD risk, was 41% higher in the powerlifters than in the controls, and 57% higher than in the runners (both P<0·01). The total area under the glucose tolerance curve during an oral glucose tolerance test (OGTT) for the powerlifters was 74% higher than for the sedentary controls (P<0·05) and 229% higher than for runners (P<0·01). Similarly, the total area under the OGTT insulin curve for the powerlifters was 68% higher than for sedentary controls and 332% higher than for the runners P<0·01). These findings suggest that middle-aged powerlifters, in marked contrast to endurance athletes, have an increased risk of developing CAD.     

Effect of medium- and long-chain triglyceride infusion on lipoprotein and hepatic lipase in healthy subjects

Plasma lipolytic activity and hydrolysis of intravenous fat were studied in six healthy subjects during infusion of a long-chain triglyceride (LCT) fat emulsion (Intralipid 20%) or of a medium-chain triglyceride (MCT)/LCT emulsion (Lipofundin MCT 20%). The fat emulsions were infused continuously at a rate of 0.17 g triglyceride kg-1 body weight (BW)h-1 for 6 h in random order at 7-day intervals. A continuous infusion of glucose (0.18 g kg-1 BW h-1) was administered for a period of 7 h and was started 1 h before the lipid infusion. Infusions of both types of fat increased plasma triglyceride (TG), free fatty acid (FFA) and lipoprotein lipase (LPL) levels and steady-state values were present during the 3rd to 5th h of infusion. MCT/LCT infusion resulted in higher plasma levels at steady-state of TG (3.63 +/- 0.45 [SEM] vs 2.73 +/- 0.45 mmol l-1; P less than 0.05), FFA (1.05 +/- 0.08 vs 0.54 +/- 0.04 mmol l-1; P less than 0.01) and LPL (4.6 +/- 0.6 vs 2.6 +/- 0.5 mU ml-1; P less than 0.05) in comparison with LCT administration. There was a positive correlation between plasma LPL activity and TG concentration (r = 0.77; P less than 0.001) when data for the two infusions were combined. Although the same amount of fat was infused on a weight basis, the molar infusion rate was 40% higher with MCT/LCT than with LCT infusion, due to differences in molecular weights (634 vs 885 Da).(ABSTRACT TRUNCATED AT 250 WORDS)     

上腹部手术前后血脂代谢的变化

①目的 探讨上腹部手术前后病人血脂的变化特点及其对机体的影响。②方法 对１３１例上腹部手术（原发性肝癌肝切除术８３例，胃大部切除术４８例）病人围手术期血脂变化进行动态监测。③结果 上腹部手术后病人血清三酰甘油、总胆固醇、载脂蛋白Ｂ均明显下降（ｔ＝３．４８６～８．４７１，Ｐ〈０．０１），原发性肝癌肝切除术后有并发症者血清总胆固醇及载脂蛋白Ｂ水平较无并发症者低（ｔ＝２．１１２～４．０２６，Ｐ〈０．０５     

Postprandial Lipid Metabolism in Normolipidemic Subjects and Patients with Mild to Moderate Hypertriglyceridemia: Effects of Test Meals Containing Saturated Fatty Acids,Mono-Unsaturated Fatty Acids,or Medium-Chain Fatty Acids

Fasting and postprandial hypertriglyceridemia are causal risk factors for atherosclerosis. The prevalence of hypertriglyceridemia is approximately 25–30% and most hypertriglyceridemic patients suffer from mild to moderate hypertriglyceridemia. Data regarding dietary interventions on postprandial triglyceride metabolism of mildly to moderately hypertriglyceridemic patients is, however, sparse. In a randomized controlled trial, eight mildly hypertriglyceridemic patients and five healthy, normolipidemic controls received three separate standardized fat-meals containing either saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA), or medium-chain fatty acids (MCFA) in a randomized order. Fasting and postprandial lipid parameters were determined over a 10 h period and the (incremental) area under the curve (AUC/iAUC) for plasma triglycerides and other parameters were determined. MCFA do not lead to a significant elevation of postprandial total plasma triglycerides and other triglyceride parameters, while both SFA (patients: p = 0.003, controls: p = 0.03 compared to MCFA) and MUFA (patients: p = 0.001; controls: p = 0.14 compared to MCFA) do lead to such an increase. Patients experienced a significantly more pronounced increase of plasma triglycerides than controls (SFA: patients iAUC = 1006 mg*h/dL, controls iAUC = 247 mg*h/dL, p = 0.02; MUFA: patients iAUC = 962 mg*h/dL, controls iAUC = 248 mg*h/dL, p = 0.05). Replacing SFA with MCFA may be a treatment option for mildly to moderately hypertriglyceridemic patients as it prevents postprandial hypertriglyceridemia.     

运动后大鼠血清中相关酶学变化的比较研究

目的通过检测运动后大鼠血清心肌肌钙蛋白I(cTnI)和磷酸肌酸激酶(CK),磷酸肌酸激酶同工酶(CK-MB),乳酸脱氢酶(LDH)并将它们进行比较,以期探讨它们在运动医学中的应用价值。方法38只SD大鼠分为对照组,游泳力竭后即刻组,游泳4.5h后6h,18h,24h组,分别测定其血清cTnI,CK,CK-MB,LDH。cTnI检测用改良Bodor双抗夹心酶联免疫法。CK-MB测定用免疫抑制法。结果①游泳力竭后即刻组,大负荷运动后6,18,24h组cTnI的OD值与对照组相比,t=1.567,ν=13,P=0.141;F=1.393,P=0.267,组间P值0.061～0.897,显示差异均无显著性。②游泳力竭后即刻组CK,CK-MB,LDH升高,与对照组相比,t值分别为4.027,10.666,9.413,P值均<0.01,差异有显著性。③大负荷运动后6h组CK,CK-MB,LDH升高,与对照组相比,P值分别是0.044,0.015,0.019,P值均<0.05,差异有显著性。结论①游泳力竭后即刻CK,CK-MB,LDH升高,但cTnI未有升高,尚需进一步动态检测cTnI。②大负荷运动后,动态检测未见有血清cTnI升高,提示未有心肌损伤。③大负荷运动后6h组出现的CK,CK-MB,LDH升高是否表明有心肌损伤应重新认识。     

Postprandial response to a fat tolerance test in young adults with a paternal history of premature coronary heart disease - the EARS II study (European Atherosclerosis Research Study)

BACKGROUND: The European Atherosclerosis Research Study (EARS) I had shown that fasting plasma concentrations of apolipoprotein B (apo B) and triglycerides were the most discriminant variables between offspring with a paternal history of coronary heart disease (CHD) and controls. The EARS II study was undertaken to investigate whether a paternal history of CHD was associated with differences in postprandial lipemia. DESIGN: Male subjects with a paternal history of CHD (cases, n = 407) and age-matched male controls (n = 415) were recruited from 14 European universities. All subjects had an oral fat tolerance test. RESULTS: In the sample as a whole, the postprandial triglyceride responses did not significantly differ between the two groups. However, in the upper tertile of fasting triglycerides, cases displayed a higher area under the curve (5.71 vs. 4.49 mmol.h L-1, P < 0.001), a higher peak (1.76 vs. 1.43 mmol L-1, P < 0.001) and a more delayed time to peak (3.15 vs. 2.91 h, P < 0.05) than controls. In the upper tertile, fasting apo B levels (P < 0.05) and triglyceride area under the curve (P = 0.002) significantly discriminated cases from controls in a multivariate analysis. Cases had also higher Lp C-III:B levels at 4 h than controls (11.2 vs. 9.9 mg dL-1, P < 0.01) and this difference remained significant after adjustment for apo B and triglyceride levels. CONCLUSIONS: These results indicate that in subjects with a moderate elevation of fasting triglycerides, an impaired postprandial response to a fat load constitutes an early biological expression of a paternal history of premature CHD.     

The relationship of TFPI, Lp(a), and oxidized LDL antibody levels in patients with coronary artery disease

OBJECTIVES: The aim of the present study was to determine and correlate tissue factor pathway inhibitor (TFPI), lipoprotein (a) (Lp(a)), oxidized low-density lipoprotein (LDL) antibody (oLAB), and thiobarbituric acid reactive substances (TBARS; as a marker of lipid peroxidation) levels in patients with coronary artery disease (CAD) and in a control group. DESIGN AND METHODS: Peripheral blood samples from patients with coronary heart disease were provided by the Department of Cardiology. Serum oLAB, Lp(a), plasma total TFPI, and plasma-free TFPI levels were determined by ELISA. Serum TBARS levels were determined by a spectrophotometric method using thiobarbituric acid. RESULTS: The CAD and the control group were matched for age and sex. Serum Lp(a), oLAB, and plasma total TFPI levels in patients with coronary heart disease were found to be significantly higher than in the control group (P < 0.001). But there was no difference in plasma-free TFPI levels between patients with CAD and the control group (P > 0.05). In patients with single (P < 0.05), double, and triple vessel (P < 0.01) disease, the mean serum Lp(a) levels were significantly higher than in the control group. On the other hand, in patients with single vessel disease (P < 0.05), double vessel disease (P < 0.05), and triple vessel disease (P < 0.001), plasma total TFPI levels were found to be significantly higher than in the control group. We also found a significant positive correlation (r = 0.28, P < 0.05) between serum Lp(a) and plasma total TFPI levels in CAD. In the patient group, TBARS, total cholesterol, triglyceride (TRG), and LDL cholesterol levels were found to be significantly higher than those in the control group. In addition, high-density lipoprotein (HDL) cholesterol levels were found to be significantly lower than the control group. CONCLUSIONS: These results suggest that elevated plasma levels of total TFPI, Lp(a), and oLAB may be useful diagnostic and monitoring markers in patients with CAD.     

Photodynamic therapy-mediated hypericin-loaded nanostructured lipid carriers against vulvovaginal candidiasis

Introduction and Aim: The indiscriminate use and adverse effects of the main conventional antifungal agents compromise the effectiveness of treating vulvovaginal candidiasis (VVC), mainly caused by the species Candida albicans. This study evaluated the effectiveness of photodynamic therapy (PDT) and the in vitro and in vivo anti-candida potential of the hypericin (HYP)-loaded nanostructured lipid carriers (NLC). Materials and Methods: Empty NLC and NLC-HYP were characterized by the dynamic light scattering technique and transmission electron microscopy to evaluate the average particle size distribution and its morphologies. The in vitro inhibition photodynamic effect of the systems was tested to reduce the planktonic viability of C. albicans. The therapeutic assay photodynamic of the systems was performed to treat VVC in mice. Results: Empty NLC and NLC-HYP presented values of average hydrodynamic diameter, polydispersity index, and ζ-potential from 136 to 133 nm, 0.16 to 0.22, and -18 to -30 mV, respectively, on day 30. Microscopically, the systems showed spherical morphologies and nanoscale particles. Furthermore, in the in vitro inhibition assay, the treatment of PDT with NLC-HYP (NLC-HYP+) showed a significant reduction of the C. albicans planktonic viability compared to YNB negative control after 5 min of LED light irradiation. In the in vivo therapeutic assay, the antifungal group (vaginal antifungal cream) and NLC-HYP+ evaluated in the dark and by PDT, respectively, had a significant log₁₀ reduction in fungal burden compared to the infected group on day 8 of the VVC treatment. Conclusion: Due to the in vitro and in vivo anti-candida potential, PDT-mediated systems can be an effective strategy in VVC therapy.