The association between the total antioxidant potential of plasma and the presence of coronary heart disease and renal dysfunction in patients with NIDDM

Oxidative stress may be an important pathogenetic factor in the development of diabetic vascular complications. The total antioxidative potential of plasma reflects the ability of an individual to resist oxidative stress. We measured the plasma total peroxyl radical-trapping potential (TRAP) and the concentrations of four plasma chain-breaking antioxidants in 81 patients with non-insulin-dependent diabetes mellitus (NIDDM) nine years after diagnosis and in 102 well-matched non-diabetic control subjects. The association between the total antioxidative potential and the presence of coronary heart disease (CHD) and diabetic kidney disease were also studied. There were no significant differences in plasma TRAP between NIDDM patients and control subjects (1250 ± 199 vs. 1224 ± 198 μM). Nor were there any significant differences in the concentrations of plasma uric acid, ascorbic acid, α-tocopherol, and protein thiols between NIDDM patients and control subjects. Patients with a low glomerular filtration rate and/or high urinary albumin excretion had elevated plasma uric acid. Plasma TRAP was not, however, associated with renal dysfunction. The plasma of NIDDM patients with CHD had a significantly higher value of unidentified antioxidative potential than that of patients without CHD. This relation was strongly dependent upon smoking. In conclusion, these data demonstrate that there are no major defects in the antioxidative potential of plasma caused by NIDDM per se. CHD and diabetic renal dysfunction were not associated with changes in plasma TRAP.     

Abnormalities of low density lipoproteins in normolipidemic type II diabetic and nondiabetic patients with coronary artery disease.

The characteristics of low density lipoproteins (LDL) of ten non-insulin-dependent diabetic (NIDDM) and ten nondiabetic patients with coronary artery disease (CAD) were investigated and compared to LDL of ten NIDDM patients without CAD and ten healthy persons. All subjects had LDL cholesterol below 160 mg/dl and serum triglycerides below 200 mg/dl. The mean LDL particle size and particle distribution profiles were analyzed by using nondenaturing polyacrylamide gradient gel electrophoresis. The LDL composition and hydrated density distribution were investigated by using density gradient ultracentrifugation. Both NIDDM and nondiabetic CAD patients tended to have larger LDL particles than NIDDM patients without CAD and healthy subjects. The increase of LDL particle size of CAD patients was due to marked enrichment of triglycerides (TG) in their LDL. The percentage content of TG in LDL of NIDDM patients with CAD was 14.5% and in LDL of nondiabetic CAD patients 13.4% compared with 7.9% in LDL of NIDDM patients without CAD and 7.2% in normal-LDL (P less than 0.05 or less between either CAD group and NIDDM without CAD or normals). The LDL TG/apolipoprotein (apo) B weight ratio was significantly higher in both CAD groups compared with LDL of the two groups without CAD (0.70 and 0.68 vs. 0.38 and 0.34, respectively, P less than 0.05, P less than 0.05 and P less than 0.01, P less than 0.01). The LDL total lipid to apoB weight ratio was similar in all four groups. Consistent with this, the hydrated density distributions of LDL in the four groups were similar, the average peak densities being 1.0346 g/ml, 1.0331 g/ml, 1.0331 g/ml, and 1.0331 g/ml, respectively. The findings of this study demonstrate that normolipidemic patients with CAD may have marked abnormalities in th eir LDL composition and these anomalies are present in both diabetic and nondiabetic patients.     

Autoantibodies against oxidized LDL are associated with severe chest pain attacks in patients with coronary heart disease

Autoantibodies against oxidized low-density lipoprotein (oxLDL) predict the progression of atherosclerosis. Several studies have shown that oxLDL is present in atherosclerotic lesions and that several factors present in active atherosclerotic plaques can oxidatively modify LDL. Oxidation of LDL induces production of autoantibodies against oxLDL (oxLDLab) that can be measured using an EIA test. Our aim was to see whether oxLDLab are associated with severe chest pain attacks in coronary heart disease (CHD) patients. Patients having two- or three-vessel CHD, as assessed by coronary angiography, and their siblings were recruited into the study (n = 568, mean age 55.8 years, range 29.3–83.2 years). Nondiabetic patients having a history of severe chest pain attacks had significantly higher oxLDLab levels (0.611 ± 0.56) than those who did not have a history of severe chest pain attacks (0.487 ± 0.40) (p = 0.027), even though age, cholesterol level, body mass index, and blood pressure were similar in both groups. However, no difference was found in oxLDLab levels in diabetic patients with or without a history of severe chest pain attacks. Increased levels of oxLDL autoantibodies are associated with severe chest pain attacks in nondiabetic patients with CHD.     

Relationships between serum levels of autoantibodies against oxidized low density lipoproteins, lipid-soluble antioxidants and apolipoprotein B in patients with coronary heart disease

High affinity IgG autoantibodies against oxidized low density lipoproteins (oxLDLs), apolipoprotein B and lipid-soluble antioxidants--alpha-tocopherol and beta-carotene, were tested in patients with coronary heart disease. Correlation relationships between these parameters were analysed. Fifty one patients with coronary heart disease (37 males/14 females) defined as Q-wave myocardial infarction and/or stenosis of more than 50%, and 51 healthy blood donors (34 males/17 females) as controls participated in this study. LDLs were isolated by density gradient ultracentrifugation and oxidized with Cu2+. OxLDLs or native LDLs (nLDLs) were used as antigens in enzyme immunoassay (ELISA) to detect IgG autoantibodies in the serum. The contents of alpha-tocopherol and beta-carotene were measured by HPLC. Apolipoprotein B was determined by immunoturbidimetry. Correlation analysis of the parameters was carried out by Spearmann's test. Alpha-tocopherol was decreased significantly in the serum of patients with coronary heart disease (2.96+/-1.63 nmol/mg serum protein vs 6.23+/-2.28 nmol/mg serum protein in Control group) (p < 0.01). Also, the serum level of beta-carotene was decreased in patients with coronary heart disease (174.0+/-95.7 pmol/mg serum protein vs 313.2+/-141.5 pmol/mg serum protein in Control group) (p < 0.01), while apolipoprotein B was increased significantly (1.20+/-0.34 g/l in patients with coronary heart disease vs 0.86+/-0.23 g/l in Control group) (p < 0.001). In a previous study we established that the mean serum level of IgG autoantibodies against oxLDLs (expressed in optical density units) was about 2.5 times higher in patients with coronary heart disease as compared to control subjects (p < 0.001). A good positive linear correlation was observed between alpha-tocopherol and apolipoprotein B levels in Control group (r = 0.78, p < 0.001), as well as in the group of patients with coronary heart disease (r = 0.42, p < 0.001). Poor nonsignificant correlations were established between all another measured parameters. In conclusion, the lipid-soluble antioxidants--alpha-tocopherol and beta-carotene, are not informative with respect to the susceptibility of the serum to oxidative modifications and as to the extent of the subsequent humoral immune response. Presumably, the reduction of the correlation coefficient between apolipoprotein-B and alpha-tocopherol in patients with coronary heart disease in comparison with control subjects could provide indirect information on modifications of apolipoprotein-B and on a decrease of its susceptibility to interact with this major lipid-soluble antioxidant in atherogenesis.     

载脂蛋白亚型与糖尿病合并冠心病的相关性研究

目的:探讨载脂蛋白亚型与糖尿病合并冠脉病变严重程度相关性,为预防及治疗糖尿病伴发的动脉粥样硬化性疾病提供新的依据。方法:选取440名心内科患者,根据冠脉造影有无冠脉狭窄及是否合并糖尿病分为四组:冠脉内膜光滑组94人(A组);单纯冠脉狭窄组108人(B组);糖尿病合并冠脉狭窄组共184人(C组);糖尿病冠脉无狭窄组44人(D组),记录患者空腹血糖、餐后血糖、传统血脂脂谱、载脂蛋白A(apoA)、载脂蛋白B(apoB)及两者的比值(apoB/apoA);采用Gensini评分比较传统血脂、apoA、apoB及与Gensini积分值的相关性。结果:与正常对照组比较,糖尿病冠脉无狭窄组apoB、apoB/apoA、LDL和TG升高,apoA和HDL降低,B组和C组apoA与Gensini积分值存在负相关(P=0.01570.05);apoB;apoB/apoA与Gensini积分值存在正相关(P0.0001);两组中,apoB与Gensini积分值相关系数最大(r=0.85795,0.85941),且apoB与Gensini积分值的相关性都强于LDL与积分值的相关性。结论:在糖尿病患者预测心血管风险上,apoB,apoA,apoB/apoA的测定可能优于传统的血脂指标。     

Flavonoids protect against oxidative damage to LDL in vitro: use in selection of a flavonoid rich diet and relevance to LDL oxidation resistance ex vivo?

The ability of a range of dietary flavonoids to inhibit low-density lipoprotein (LDL) oxidation in vitro was tested using a number of different methods to assess oxidative damage to LDL. Overall quercetin was the most effective inhibitor of oxidative damage to LDL in vitro. On this basis, a diet enriched with onions and black tea was selected for a dietary intervention study that compared the effect on the Cu²⁺ ion-stimulated lag-time of LDL oxidation ex vivo in healthy human subjects of a high flavonoid diet compared with a low flavonoid diet. No significant difference was found in the Cu²⁺ ion-stimulated lag-time of LDL oxidation ex vivo between the high flavonoid and low flavonoid dietary treatments (48 ± 1.6 min compared to 49 ± 2.1 min).     

Low density lipoprotein metabolism in hypertriglyceridemic and normolipidemic patients with coronary heart disease

The turnover rates of low density lipoprotein-apolipoprotein B (LDL-apoB) were determined in 32 men with coronary heart disease (CHD) and 11 control men with normal plasma lipids. Thirty patients with CHD had normal levels of LDL-cholesterol (LDL-C); of these patients, 9 had hypertriglyceridemia and 21 had normal plasma lipids. Mean concentrations of total cholesterol and LDL-C were similar among the control subjects and CHD patients, although the latter had significantly lower HDL-C. In control subjects, transport rates and fractional catabolic rates (FCR) of LDL-B were 10.6 +/- 0.5 (SEM) mg/kg-day and 0.31 +/- 0.01 pools/day, respectively. In 10 hypertriglyceridemic patients with CHD, transport rates were 21.7 +/- 1.7 mg/kg-day, and FCRs averaged 0.56 +/- 0.06 pools/day; both were significantly higher than normal (P less than 0.05). Six normolipidemic patients also had abnormally high transport rates of LDL-apoB (19.4 +/- 2.8 mg/kg-day) and FCRs (0.51 +/- 0.03 pools/day); again both were higher than normal. The remaining 16 normolipidemic patients with CHD had normal transport rates (9.9 +/- 0.6 mg/kg-day) and FCRs (0.28 +/- 0.01 pools/day). Thus, hypertriglyceridemic patients with CHD and a portion of normolipidemic patients with CHD were characterized by increases in both transport and fractional catabolic rate of LDL-apoB; these abnormalities in LDL metabolism may have contributed to their coronary heart disease. However, the majority of normolipidemic patients with CHD did not show a distinct defect in their LDL metabolism.     

Isolation of desialylated low density lipoproteins from the blood of patients with ischemic heart disease by affinity chromatography

The attempt was performed to isolate desialylated low density lipoproteins (LDL) from the blood of healthy subjects and patients with coronary heart disease by affinity chromatography with immobilized agglutinin of Ricinus communis, a lectin that interacts specifically with galactose residues. A part of LDL was bound to sorbent and could be replaced by galactose but not other saccharide constituents of the LDL molecule. Bound LDL subfraction had a 2-3-fold lower content of desialylated LDL in CAD patients was about 3-fold higher than in healthy subjects. Desialylated LDL induced a 2- to 4-fold increase of total cholesterol content in cultured human aortic intimal cells, whereas unbound LDL had no effect on intracellular cholesterol level. It is assumed that the subfraction of desialylated LDL may be responsible for the atherogenic properties of LDL in CAD patients.     

The fatty acid distribution in low density lipoprotein in diabetes

Atherosclerosis is commonly found in diabetes. There is an association between small dense low density lipoprotein (LDL) phenotype, which is more prevalent in the diabetic state, and atherosclerosis. Small dense LDL is more easily oxidised and it is possible that fatty acid compositional changes, particularly an increase in polyunsaturated fatty acids, could underlie this association. However, there is little information about fatty acids in the different LDL phenotypes in the literature. This study examined LDL subfraction composition in 18 non-insulin-dependent diabetic (NIDDM) patients and 11 control subjects. LDL was isolated and fractionated into LDL 1, 2 and 3 by density gradient ultracentrifugation. NIDDM patients had significantly more fatty acids in all LDL subfractions than control subjects (P<0.01). Palmitic and linoleic acid were significantly greater in all subfractions in the diabetic patients compared to control subjects (P<0.01) and palmitoleic and oleic acids were also greater in LDL1 and LDL2 in diabetic patients (P<0.01). We conclude that in NIDDM fatty acids are increased in all LDL subfractions and this may be the reason for the increased atherosclerosis in diabetes irrespective of phenotype.     

The fatty acid distribution in low density lipoprotein in diabetes.

Atherosclerosis is commonly found in diabetes. There is an association between small dense low density lipoprotein (LDL) phenotype, which is more prevalent in the diabetic state, and atherosclerosis. Small dense LDL is more easily oxidised and it is possible that fatty acid compositional changes, particularly an increase in polyunsaturated fatty acids, could underlie this association. However, there is little information about fatty acids in the different LDL phenotypes in the literature. This study examined LDL subfraction composition in 18 non-insulin-dependent diabetic (NIDDM) patients and 11 control subjects. LDL was isolated and fractionated into LDL 1, 2 and 3 by density gradient ultracentrifugation. NIDDM patients had significantly more fatty acids in all LDL subfractions than control subjects (P<0.01). Palmitic and linoleic acid were significantly greater in all subfractions in the diabetic patients compared to control subjects (P<0.01) and palmitoleic and oleic acids were also greater in LDL1 and LDL2 in diabetic patients (P<0.01). We conclude that in NIDDM fatty acids are increased in all LDL subfractions and this may be the reason for the increased atherosclerosis in diabetes irrespective of phenotype.     

Studies on the association of NIDDM in Japanese patients with hyperthyroid Graves' disease.

We attempted to analyze the association of hyperthyroid Graves' disease with non-insulin-dependent diabetes mellitus (NIDDM). Forty-nine patients (23 males and 26 females; 7.6%) of a total of 647 patients with hyperthyroid Graves' disease had NIDDM, several years before or after Graves' disease was diagnosed. Only 1 patient had insulin-dependent diabetes mellitus. Compared with the general Japanese population (n = 9,133), the incidence of NIDDM (n = 348; 3.9%) in patients with Graves' disease was higher in all age groups. Only 4 patients (8.2%) of the 49 hyperthyroid patients with NIDDM had a history of being overweight (body mass index > 25). In contrast, 276 (79.9%) of the 348 diabetic patients were currently or previously overweight. Moreover, the incidence of a family history of diabetes (13 of the 49 hyperthyroid Graves' patients with NIDDM; 26.5%) was also lower in the patients with NIDDM in the general Japanese population (50% incidence). The male:female ration in patients with Graves' disease and NIDDM was 1:1.1; much different from that in the total Graves' disease population (1:4.1). Analysis of the HLA loci A, B, C, DR and DQ (35 determinations) in 35 hyperthyroid patients with NIDDM and in 386 subjects from the general population revealed a highly significant difference between them in the incidence of HLA-Cw4, -DR2, -DQw1, -DQw3 and -DQw4. This study suggests that there was an association of Graves' disease with NIDDM. A significant association of HLA-DR and -DQ loci was observed in hyperthyroid Graves' patients with NIDDM.     

Serum lipoproteins,lipid peroxides and prostacyclin biosynthesis in patients with coronary hear diseases

Serum low-density lipoproteins (LDL)_and high-density lipoproteins (HDL) were prepared by gradient ultracentrifugation and dialysis from 12 healthy subjects and 15 patients with coronary heart disease and hyperlipoproteinemia. In both lipoprotein fractions cholesterol and lipid peroxides were determined. The effect of these lipoproteins on spontaneous prostacyclin biosynthesis in rat aortic slices was studied.Serum lipoproteins were susceptible to peroxidation during the preparation procedure. LDL were more prone to peroxidation than HDL. Little lipid peroxidase were formed in lipoproteins when calcium ions had been removed by EDTA, and when butylated hydroxytoluene (BHT) was present at all stages of their preparation. LDL when prepared without these precautions either from healthy subjects or from patients with coronary heart diseases markedly suppressed prostacyclin generation by rat aortic slices. This inhibition to LDL-lipid peroxides. Peroxide-low LDL prepared from most of the healthy subjects and patients with coronary heart disease and concomitant hyperlipoproteinemia, did not inhibit prostacyclin biosynthesis. However, in one quarter of the patients. LDL was inhibitory. Consequently, in some patients with coronary heart disease, there operate unknown mechanisms which are responsible for the inhbibitory activity of LDL on prosctacylin generation.     

Effects of altitude on exercise level and heart rate in patients with coronary artery disease and healthy controls

Background. To evaluate the safety and effects of high altitude on exercise level and heart rate in patients with coronary artery disease compared with healthy controls. Methods. Eight patients with a history of an acute myocardial infarction (ejection fraction >5%) with a low-risk score were compared with seven healthy subjects during the Dutch Heart Expedition at the Aconcagua in Argentina in March 2007. All subjects underwent a maximum exercise test with a cycle ergometer at sea level and base camp, after ten days of acclimatisation, at an altitude of 4200 m. Exercise capacity and maximum heart rate were compared between groups and within subjects. Results. There was a significant decrease in maximum heart rate at high altitude compared with sea level in both the patient and the control group (166 vs. 139 beats/min, p<0.001 and 181 vs. 150 beats/min, p<0.001). There was no significant difference in the decrease of the exercise level and maximum heart rate between patients and healthy controls (-31 vs. -30%, p=0.673). Conclusion. Both patients and healthy controls showed a similar decrease in exercise capacity and maximum heart rate at 4200 m compared with sea level, suggesting that patients with a history of coronary artery disease may tolerate stay and exercise at high altitude similarly to healthy controls. (Neth Heart J 2010;18:118-21.)     

Seasonality and coronary heart disease deaths in United States firefighters

United States firefighters have a high on-duty fatality rate, and coronary heart disease is the leading cause. Seasonality affects the incidence of cardiovascular events in the general population, but its effects on firefighters are unknown. This study statistically examined the seasonal and annual variation of all on-duty coronary heart disease deaths among US firefighters between 1994 and 2004 using the chi-square distribution and Poisson regression model of the monthly fatality counts. It also examined the effect of ambient temperature (apparent as well as wind chill temperature) on coronary heart disease fatalities during the study span using a time-stratified, case-crossover study design. When grouped by season, we observed the distribution of the 449 coronary heart disease fatalities to show a relative peak in winter (32%) and relative nadir in spring (21%). This pattern was significantly different (p=0.005) from the expected distribution under the null hypothesis of season having no effect. The pattern persisted in additional analyses, stratifying the deaths by the type of duty in which the firefighters were engaged at the time of their deaths. In the Poisson regression model of the monthly fatality counts, the overall goodness-of-fit between the actual and predicted case counts was excellent (χ₄²=16.63; p=0.002). Two distinct peaks were detected: one in January-February and the other in August-September. Overall temperature was not associated with increased risk of on-duty death. After allowing for different effects of temperature in mild/hot versus cold periods, a 1°C increase was not protective in cold weather; nor did it increase the risk of death in warmer weather. The findings of this study reveal statistical evidence for excess coronary heart disease deaths among firefighters during winter; however, the temporal pattern of coronary heart disease deaths was not linked to temperature variation. The seasonal pattern was also found to be independent of duty-related risks.     

瑞舒伐他汀对老年冠心病伴高脂血症患者血脂及 高敏C 反应蛋白的影响研究

目的：观察老年冠心病伴高脂血症患者应用瑞舒伐他汀治疗后的血脂及高敏C反应蛋白变化。方法：随机将2012 年7 月～ 2013 年6 月在本院治疗的68 例冠心病合并高脂血症患者分为两组,对照组采用常规治疗方法治疗,在对照组的基础上,治疗组 给予瑞舒伐他汀,治疗周期均为2 个月,观察两组治疗前后的血脂及高敏C 反应蛋白水平的变化,并统计治疗期间两组不良反应 发生情况。结果：两组治疗前的TC、TG、LDL-C、HDL-C 差异不显著,P＞0.05;而治疗后,两组的TC、TG、LDL-C水平均出现下降, HDL-C 水平上升趋势,但观察组治疗后的TC、TG、LDL-C 水平均明显低于对照组的（P＜0.05）,观察组治疗后的HDL-C 水平均 明显高于对照组的（P＜0.05）。治疗组治疗前的hs-CRP 为（3.86± 1.12）mg/L,对照组治疗前的hs-CRP 为（3.82± 0.84）mg/L,两组 差异不显著（P＞0.05）,治疗后,两组的hs-CRP 均出现下降,治疗组的hs-CRP 为（2.57± 0.66）mg/L,对照组的hs-CRP 为（3.23± 0.66）mg/L,两组差异显著（P＜0.05）。两组治疗后均出现轻微的不良反应症状,治疗组不良反应发生率为8.82%,对照组不良反应 发生率为23.53%,两组差异不显著（x2=0.497,P=0.780＞0.05）。结论：瑞舒伐他汀能有效地改善冠心病合并高脂血症的血脂,降低 高敏C 反应蛋白,值得在冠心病合并高脂血症临床治疗中更广泛地应用。     

Plasma adiponectin concentrations in patients with chronic renal failure: relationship with metabolic risk factors and ischemic heart disease.

AIMS: To compare plasma adiponectin levels between healthy controls and patients with chronic renal failure and to examine for a relationship between plasma adiponectin levels and ischemic heart disease as well as aortic distensibility which is an early marker of atherosclerosis. METHODS: We included 89 patients with CRF (45 on and 44 not on hemodialysis) and 70 controls in a cross-sectional study. Plasma adiponectin levels were measured by radioimmunoassay. Aortic distensibility was assessed by high-resolution ultrasonography. RESULTS: Plasma adiponectin levels were significantly almost twice as high in patients with renal failure compared to controls (9.7 +/- 1.1 vs. 5.4 +/- 0.6 microg/ml, p < 0.0001). No significant differences were found between renal patients on hemodialysis and not on hemodialysis (p = 0.71). Multivariate linear regression analysis in the renal patient group demonstrated a significant negative relationship between plasma adiponectin levels and ischemic heart disease (p = 0.02). The same analysis in the control subjects group showed a significant, negative relationship between plasma adiponectin levels and body mass index (p = 0.02) and a highly significant positive relationship with the high density lipoprotein cholesterol (p < 0.0001). In the total study population, glomerular filtration rate was the only independent predictor of plasma adiponectin concentrations. Aortic distensibility was lower in renal patients than in controls at a high level of significance (p < 0.0001). However, no significant relationship could be found between plasma adiponectin and aortic distensibility in either the controls or the renal patients. CONCLUSIONS: Plasma adiponectin levels are almost twice as high in patients with chronic renal failure in comparison with healthy controls, but not different between renal patients on and those not on hemodialysis. In addition, low plasma adiponectin levels are strongly associated with ischemic heart disease, but not with aortic distensibility in chronic renal failure.     

Impaired resistance to oxidation of low density lipoprotein in cystic fibrosis: Improvement during vitamin E supplementation

Antioxidants such as vitamin E protect unsaturated fatty acids of LDL against oxidation. In the ex vivo model used, LDL was exposed to Cu²⁺ ions, a potent prooxidant capable of initiating the oxidation of LDL. The lag time, indicating the delay of conjugated diene formation in LDL due to antioxidant protection, was measured in 54 cystic fibrosis (CF) patients with plasma -tocopherol levels below (Group A, n = 30) or above (Group B, n = 24) 15.9 μmol/L (mean - 2 SD of Swiss population). Patients were reevaluated after 2 months on 400 IU/d of oral RRR--tocopherol. In group A, -tocopherol concentrations in LDL increased significantly from 3.2 ± 1.6 mol/mol LDL to 8.2 ± 2.8 mol/mol (P < 0.001) and lag times increased from 79 ± 33, min to 126 ± 48 min (P < 0.001), whereas in the vitamin E sufficient group B no further increase neither in LDL -tocopherol concentrations or in lag times was observed. LDL oleic acid concentrations were higher, and linoleic acid concentrations were lower in patients than in controls. After efficient vitamin E supplementation, lag times were positively related to LDL -tocopherol (P < 0.01) and negatively to LDL linoleic and arachidonic acid content (P < 0.001). The maximum rate of oxidation correlated positively with linoleic and arachidonic acid concentrations, as did the maximum conjugated diene absorbance. These results indicate that LDL resistance to oxidation is impaired in vitamin E deficient CF patients but can be normalized within 2 months when -tocopherol is given in sufficient amounts. Linoleic and arachidonic acid content exhibit a major influence on the LDL resistance to oxidation.     

OSAS对冠心病患者的血糖和血脂水平的影响

目的:探讨阻塞性睡眠呼吸暂停综合征(Obstructive sleep apnea syndrome,OSAS)对冠心病患者血糖和血脂的影响。方法:纳入我科住院的明确诊断冠心病患者共168人,根据呼吸暂停低通气指数(Apnea-hypopnea index,AHI)共分2组:冠心病组133例,冠心病合并OSAS组45例(轻度OSAS组16例;中度OSAS组18例,重度OSAS组12例)。对比分析冠心病组和冠心病合并OSAS组患者血脂及血糖水平及其相关性。结果:BMI、LDL、HDL在四组间差异有统计学意义(P0.05)。冠心病合并OSAS的BMI、LDL、HDL明显高于冠心病组,各组间BMI差异有统计学意义(P0.05)。FPG、HOMA-I、RHb A1、OX-LDL、AHI在冠心病组和冠心病合并轻度OSAS组之间差异无统计学意义(P0.05)。FPG、HOMA-I、RHb A1、OX-LDL、AHI在OSAS轻、中、重各组间差异有统计学意义(P0.05)。冠心病合并OSAS患者AHI和BMI、LDL、FPG、HOMA-I、OX-LDL呈正相关关系(P0.05)。结论:OSAS增加了冠心病患者血脂水平和糖尿病的风险,及机制可能与胰岛素抵抗和OX-LDL水平增高有关。     

Intracellular magnesium in elderly patients with heart failure: Effects of diabetes and renal dysfunction

Hypomagnesemia is frequent in diabetes mellitus (DM), while renal dysfunction (RD) may be associated with hypermagnesemia. Severe cardiac arrhythmias and other adverse clinical manifestations are frequent in heart failure (HF), in DM and in RD. Depletion of intracellular magnesium (icMg), which may coexist with normal serum Mg, might contribute to these deleterious effects. However, icMg content in normomagnesemic HF patients with RD or DM has not been studied. We assessed total icMg in peripheral blood mononuclear cells (PBMC) from 80 normomagnesemic furosemide-treated HF patients who were divided as follows: subgroups A (DM), B (RD), C (DM and RD), and D (free of DM or RD). PBMC from 18 healthy volunteers served as controls. IcMg content (μg/mg cell protein) in HF was lower compared to controls (1.68±0.2 vs. 2.4±0.39, p<0.001). In the entire HF group, a significant inverse correlation was evident between icMg and serum creatinine (r=−0.37) and daily furosemide dosages (r=−0.121). IcMg in the HF subgroups A, B, C, and D was 1.79±0.23, 1.57±0.23, 1.61±0.25, and 1.79±0.39, respectively (p=0.04 between A and B, p=0.08 between B and D, and non-significant in the remaining comparisons). Serum Mg, potassium, calcium, furosemide dosages and left ventricular ejection fraction were comparable in all subgroups. In conclusion, icMg depletion was demonstrable in PBMC, which may be responsible for some of the adverse clinical manifestations in HF patients. In particular, icMg depletion in RD might contribute to cardiac arrhythmias in this patient group. Mg supplementation to normomagnesemic HF patients might therefore prove beneficial.