Lack of effect of dietary chromium supplementation on glucose tolerance, plasma insulin and lipoprotein levels in patients with type 2 diabetes

Chromium is essential for the regulation of insulin action, thereby influencing carbohydrate and lipid metabolism. An uncontrolled pilot study was designed to measure the habitual daily intake of chromium in a group of healthy individuals with type 2 diabetes and to monitor the effect of daily supplementation with high chromium yeast on glucose tolerance, plasma insulin and lipoproteins. Twelve free-living adults with type 2 diabetes underwent a glucose tolerance test (GTT) on recruitment, at 4 weeks (after a 7-d duplicate diet collection) and at 12 weeks (following 8 weeks daily supplementation with 100 micrograms of chromium). Urine samples were collected on the day before and the day of each GTT. Blood samples were taken at half hourly intervals for 3 hours during the GTT and the plasma glucose, cholesterol, triglyceride, HDL, LDL and insulin concentration measured. The chromium content of diets and urine samples was determined. Fasting glucose concentrations and glucose area under the curve profiles did not alter significantly post supplementation with the chromium rich yeast. No significant changes in insulin and lipoprotein concentrations were observed. The results of this study do not support the hypothesis that individuals with type 2 diabetes benefit from yeast-based chromium supplements (100 micrograms/day).     

Dietary intakes and plasma concentrations of carotenoids and tocopherols in relation to glucose metabolism in subjects at high risk of type 2 diabetes: the Botnia Dietary Study

BACKGROUND: The role of antioxidants in the pathogenesis of type 2 diabetes is uncertain. OBJECTIVE: We evaluated cross-sectional relations of dietary intakes and plasma concentrations of antioxidants with glucose metabolism in a high-risk population. DESIGN: The subjects were 81 male and 101 female first- and second-degree, nondiabetic relatives of patients with type 2 diabetes. Antioxidant intake data were based on 3-d food records. Subjects taking supplements containing beta-carotene or alpha-tocopherol were excluded. Plasma antioxidant concentrations were measured by HPLC. By using multiple linear regression analysis and adjusting for demographic, anthropometric, and lifestyle covariates, we studied whether dietary and plasma alpha- and beta-carotene, lycopene, and alpha- and gamma-tocopherol were related to fasting and 2-h concentrations of glucose and nonesterified fatty acids during an oral-glucose-tolerance test, to the homeostasis model assessment index of insulin resistance, and to measures of beta cell function (incremental 30-min serum insulin concentration during an oral-glucose-tolerance test and first-phase insulin secretion during an intravenous-glucose-tolerance test). RESULTS: In men, dietary carotenoids were inversely associated with fasting plasma glucose concentrations (P < 0.05), plasma beta-carotene concentrations were inversely associated with insulin resistance (P = 0.003), and dietary lycopene was directly related to baseline serum concentrations of nonesterified fatty acids (P = 0.034). In women, dietary alpha-tocopherol and plasma beta-carotene concentrations were inversely and directly associated, respectively, with fasting plasma glucose concentrations (P < 0.05). In both sexes, cholesterol-adjusted alpha-tocopherol concentrations were directly associated with 2-h plasma glucose concentrations (P < 0.05). CONCLUSION: The data suggest an advantageous association of carotenoids, which are markers of fruit and vegetable intake, with glucose metabolism in men at high risk of type 2 diabetes.     

Dietary antioxidants and glucose metabolism

PURPOSE OF REVIEW: Oxidative stress seems to play a pathogenic role in the vicious circle linking obesity, insulin resistance and type 2 diabetes. Hypothetically, dietary antioxidants should decrease oxidative stress and therefore improve glucose metabolism. However, many interventional trials evaluating the effect of antioxidant supplementation on insulin resistance, plasma glucose levels and risk of type 2 diabetes gave inconsistent results. RECENT FINDINGS: Many studies have recently demonstrated a positive effect of vitamin supplementation and of food enriched in antioxidant (seafood, whole nut, etc.) on markers of oxidative stress, insulin resistance, fasting plasma glucose and incidence of diabetes. The present paper critically reviews the consolidated notions on dietary antioxidant in view of the recent evidences. SUMMARY: Although a definitive estimation of the impact of dietary antioxidants on glucose metabolism is still lacking, food with high antioxidant concentrations seems to have a protective effect, improving oxidative stress-mediated detrimental effects on the vicious circle among obesity, insulin resistance and redox imbalance.     

Relation between insulin resistance and plasma concentrations of lipid hydroperoxides, carotenoids, and tocopherols

BACKGROUND: It is not known whether total circulating lipid hydroperoxides are increased in insulin-resistant individuals and whether this correlates with depletion of liposoluble antioxidant vitamins that are consumed during lipid peroxidation. OBJECTIVE: The goal of this study was to define the relation between resistance to insulin-mediated glucose disposal and plasma concentrations of lipid hydroperoxides and liposoluble antioxidant vitamins in healthy volunteers. DESIGN: Insulin-mediated glucose disposal was determined in 36 healthy, nondiabetic volunteers by measuring their steady-state plasma insulin (SSPI) and glucose (SSPG) concentrations in response to a 180-min constant infusion of octreotide, insulin, and glucose. In addition, fasting plasma concentrations of lipid hydroperoxides and liposoluble antioxidant vitamins were determined by using the FOX 2 assay and liquid chromatography. RESULTS: Statistically significant direct relations were observed between SSPG and mean arterial blood pressure (r = 0.44, P: = 0.008) and plasma lipid hydroperoxide concentrations (r = 0.42, P: = 0.01), whereas significant inverse correlations were found between SSPG and alpha-carotene (r = -0.58, P: = 0.0002), beta-carotene (r = -0.49, P: = 0.004), lutein (r = -0.35, P: = 0.04), alpha-tocopherol (r = -0. 36, P: = 0.04), and delta-tocopherol (r = -0.45, P: = 0.007). CONCLUSIONS: Variations in insulin-mediated glucose disposal in healthy individuals are significantly related to plasma concentrations of lipid hydroperoxides and liposoluble antioxidant vitamins. These findings suggest that total plasma lipid peroxidation is increased in insulin-resistant individuals at an early, preclinical stage, ie, well before the development of glucose intolerance and type 2 diabetes.     

Supplementation with mixed tocopherols increases serum and blood cell gamma-tocopherol but does not alter biomarkers of platelet activation in subjects with type 2 diabetes

BACKGROUND: Some studies have shown potential benefit of vitamin E on platelet function, but several clinical trials failed to show improved cardiovascular outcome with alpha-tocopherol supplementation. Gamma-tocopherol, a major dietary form of vitamin E, may have protective properties different from those of alpha-tocopherol. OBJECTIVE: We compared the effects of supplementation with alpha-tocopherol (500 mg) and a gamma-tocopherol-rich compound (500 mg, containing 60% gamma-tocopherol) on serum and cellular tocopherol concentrations, urinary tocopherol metabolite excretion, and in vivo platelet activation in subjects with type 2 diabetes. DESIGN: Fifty-eight subjects were randomly assigned to receive either 500 mg alpha-tocopherol/d, 500 mg mixed tocopherols/d, or matching placebo. Serum, erythrocyte, and platelet tocopherol and urinary metabolite concentrations were measured at baseline and after the 6-wk intervention. Soluble CD40 ligand, urinary 11-dehydro-thromboxane B2, serum thromboxane B2, soluble P-selectin, and von Willebrand factor were measured as biomarkers of in vivo platelet activation. RESULTS: Serum alpha-tocopherol increased with both tocopherol treatments. Serum and cellular gamma-tocopherol increased 4-fold (P < 0.001) in the mixed tocopherol group, whereas red blood cell gamma-tocopherol decreased significantly after alpha-tocopherol supplementation. Excretion of alpha-carboxyethyl-hydroxychroman increased significantly after supplementation with alpha-tocopherol and mixed tocopherols. Excretion of gamma-carboxyethyl-hydroxychroman increased significantly after supplementation with mixed tocopherols and after that with alpha-tocopherol, which may reflect the displacement of gamma-tocopherol by alpha-tocopherol due to incorporation of the latter into lipoproteins in the liver. Neither treatment had any significant effect on markers of platelet activation. CONCLUSIONS: Supplementation with alpha-tocopherol decreased red blood cell gamma-tocopherol, whereas mixed tocopherols increased both serum alpha-tocopherol and serum and cellular gamma-tocopherol. Changes in serum tocopherol closely reflect changes in cellular concentrations of tocopherols after supplementation.     

A randomized study to establish the effects of spirulina in type 2 diabetes mellitus patients

Spirulina is a microscopic and filamentous cyanobacterium that contains essential amino acids, essential fatty acids, vitamins, minerals and anti-oxidative components. The purpose of this study was to examine effects of spirulina intervention in Korean patients with type 2 diabetes. The subjects were 37 type 2 diabetic patients who visited a diabetic clinic in Seoul and randomly assigned into spirulina (8 g/day) or control group. During the intervention period of 12 weeks, subjects were asked to keep usual diet and prohibited to take any functional foods or dietary supplements. Spirulina supplementation for 12 weeks did not affect anthropometric parameters, however, lowered plasma triglycerides level significantly (p<0.05). Spirulina supplementation also resulted in a significant reduction in plasma malondialdehyde level (p<0.05) and an increase in plasma adiponectin level (p<0.1). The lipid lowering effect of spirulina supplementation was different according to serum lipid levels of the subjects before entering the intervention. The subjects with higher initial triglyceride level showed higher reduction in plasma triglyceride and blood pressure. The subjects with higher initial total cholesterol and LDL-cholesterol level showed higher reduction in plasma concentrations of total cholesterol, LDL-cholesterol, IL-6, and blood pressure. It seems that spirulina supplementation is more effective in subjects with dyslipidemia. This study provides the evidence for beneficial effects of spirulina supplementation on blood lipid profiles, inflammatory variables, and antioxidant capacity in Korean patients with type 2 diabetes. The results suggest that spirulina is a promising agent as a functional food for diabetes management.     

胰岛素泵治疗重症高龄2型糖尿病患者临床分析

目的 比较胰岛素泵持续皮下输注胰岛素与多次皮下注射胰岛素对重症高龄2型糖尿病患者的疗效与安全性.方法 将37例在重症监护室（ICU）住院的重症高龄2型糖尿病患者按随机数字表法分为观察组（19例）和对照组（18例）,观察组用胰岛素泵持续皮下输注赖脯胰岛素,对照组用赖脯胰岛素三餐前及甘精胰岛素晚上睡前常规皮下注射,两组患者及家属均给予糖尿病教育、根据病情合适的糖尿病饮食,比较治疗前后两组患者的血糖变化、胰岛素用量、血糖控制达标时间、低血糖发生率及住院时间.结果 治疗后观察组空腹血糖为（7.2±1.2）mmo1/L,餐后2h血糖为（9.4±1.2） mmol/L,睡前血糖为（9.4±1.3） mmol/L,对照组分别为（8.5±3.0）、（10.0±2.4）、（10.2±2.4）mmol/L,治疗后两组患者空腹血糖、餐后2h血糖及睡前血糖均较治疗前显著下降,且两组治疗后比较差异有统计学意义（P＜0.05）.观察组患者血糖控制达标时间为（5.4±2.5）d,胰岛素用量为（43±9）U/d,而对照组分别为（12.8±3.8）d、（55±10）U/d,两组比较差异有统计学意义（P＜0.05）.观察组未见低血糖发生.结论 胰岛素泵持续皮下输注胰岛素与多次皮下注射胰岛素对重症高龄2型糖尿病均具有较好的疗效与安全性,且胰岛素泵持续皮下输注胰岛素更利于此类患者血糖控制及改善病情.     

Effect of the magnetized water supplementation on blood glucose,lymphocyte DNA damage,antioxidant status,and lipid profiles in STZ-induced rats

This study investigated the effects of magnetized water supplementation on blood glucose, DNA damage, antioxidant status, and lipid profiles in streptozotocin (STZ)-induced diabetic rats. There were three groups of 4-week-old male Sprague-Dawley rats used in the study: control group (normal control group without diabetes); diabetes group (STZ-induced diabetes control); and magnetized water group (magnetized water supplemented after the induction of diabetes using STZ). Before initiating the study, diabetes was confirmed by measuring fasting blood glucose (FBS > 200 dl), and the magnetized water group received magnetized water for 8 weeks instead of general water. After 8 weeks, rats were sacrificed to measure the fasting blood glucose, insulin concentration, glycated hemoglobin level, degree of DNA damage, antioxidant status, and lipid profiles. From the fourth week of magnetized water supplementation, blood glucose was decreased in the magnetized water group compared to the diabetes group, and such effect continued to the 8th week. The glycated hemoglobin content in the blood was increased in the diabetes group compared to the control group, but decreased significantly in the magnetized water group. However, decreased plasma insulin level due to induced diabetes was not increased by magnetized water supplementation. Increased blood and liver DNA damages in diabetes rats did significantly decrease after the administration of magnetized water. In addition, antioxidant enzyme activities and plasma lipid profiles were not different among the three groups. In conclusion, the supplementation of magnetized water not only decreased the blood glucose and glycated hemoglobin levels but also reduced blood and liver DNA damages in STZ-induced diabetic rats. From the above results, it is suggested that the long-term intake of the magnetized water over 8 weeks may be beneficial in both prevention and treatment of complications in diabetic patients.     

血浆抗素水平与胰岛素抵抗的关系研究

目的:探讨血浆抗素(resistin)与肥胖、胰岛素抵抗及糖尿病之间的关系。方法:对型糖尿病(DM)组122例、糖耐量低减组(IGT)56例、糖耐量正常对照组(NGT)122例,采用争性酶联免疫分析法检测空腹血浆抗素浓度;同时测定血脂水平、空腹血浆葡萄糖浓度(FPG)和浆胰岛素浓度(FINS);测量身高、体重、腰围、血压(SBP、DBP),计算体质指数(BMI)、体脂百比(%Fat)、稳态模型胰岛素抵抗指数(HOMA-IR)。结果:与糖耐量正常组比较,糖尿病组体脂百分比甘油三酯(TG)、总胆固醇(TC)、血浆抗素水平、胰岛素抵抗指数较高(P<0.05)。相关分析显示浆Resistin水平与体质指数、体脂百分比、腰围、总胆固醇、胰岛素、血糖、胰岛素抵抗指数呈正关,调整BMI、年龄后,血浆抗素水平仍与胰岛素、血糖、胰岛素抵抗指数呈正相关。结论:Ⅱ型尿病患者血浆抗素水平较高,血浆抗素水平与胰岛素、空腹血糖水平及胰岛素抵抗指数相关,提示素是胰岛素抵抗发生的一个重要危险因素,在胰岛素抵抗与糖尿病之间建立联系。     

Conjugated linoleic acid supplementation, insulin sensitivity, and lipoprotein metabolism in patients with type 2 diabetes mellitus

BACKGROUND: Some animal studies have suggested that conjugated linoleic acid (CLA) supplementation may have therapeutic potential with respect to insulin sensitivity and lipid metabolism, which are important cardiovascular disease (CVD) risk factors associated with type 2 diabetes mellitus. OBJECTIVE: We investigated the effect of CLA supplementation on markers of glucose and insulin metabolism, lipoprotein metabolism, and inflammatory markers of CVD in subjects with type 2 diabetes. DESIGN: The study was a randomized, double-blind, placebo-controlled trial. Thirty-two subjects with stable, diet-controlled type 2 diabetes received CLA (3.0 g/d; 50:50 blend of cis-9,trans-11 CLA and trans-10,cis-12 CLA) or control for 8 wk. A 3-h 75-g oral-glucose-tolerance test was performed, and fasting plasma lipid concentrations and inflammatory markers were measured before and after the intervention. RESULTS: CLA supplementation significantly increased fasting glucose concentrations (6.3%; P < 0.05) and reduced insulin sensitivity as measured by homeostasis model assessment, oral glucose insulin sensitivity, and the insulin sensitivity index (composite) (P = 0.05). Total HDL-cholesterol concentrations increased by 8% (P < 0.05), which was due to a significant increase in HDL(2)-cholesterol concentrations (P < 0.05). The ratio of LDL to HDL cholesterol was significantly reduced (P < 0.01). CLA supplementation reduced fibrinogen concentrations (P < 0.01) but had no effect on the inflammatory markers of CVD (C-reactive protein and interleukin 6). CONCLUSIONS: CLA supplementation had an adverse effect on insulin and glucose metabolism. Whereas CLA had positive effects on HDL metabolism and fibrinogen, a therapeutic nutrient should not be associated with potentially adverse effects on other clinical markers of type 2 diabetes.     

Circulating interleukin-6 in relation to adiposity, insulin action, and insulin secretion.

OBJECTIVE: Plasma concentrations of interleukin-6 (IL-6), a proinflammatory cytokine produced and released in part by adipose tissue, are elevated in people with obesity and type 2 diabetes. Because recent studies suggest that markers of inflammation predict the development of type 2 diabetes, we examined whether circulating plasma IL-6 concentrations were related to direct measures of insulin resistance and insulin secretory dysfunction in Pima Indians, a population with high rates of obesity and type 2 diabetes. RESEARCH METHODS AND PROCEDURES: Fasting plasma IL-6 concentrations (enzyme-linked immunosorbent assay), body composition (DXA), insulin action (M; hyperinsulinemic euglycemic clamp), and acute insulin secretory responses to glucose (25 g intravenous glucose tolerance test) were measured in 58 Pima Indians without diabetes (24 women, 34 men). RESULTS: Fasting plasma IL-6 concentrations were positively correlated with percentage of body fat (r = 0.26, p = 0.049) and negatively correlated with M (r = -0.28, p = 0.031), but were not related to acute insulin response (r = 0.13, p = 0.339). After adjusting for percentage of body fat, plasma IL-6 was not related to M (partial r = -0.23, p = 0.089). DISCUSSION: Fasting plasma IL-6 concentrations are positively related to adiposity and negatively related to insulin action in Pima Indians. The relationship between IL-6 and insulin action seems to be mediated through adiposity.     

Antioxidant effects of zinc supplementation in Tunisians with type 2 diabetes mellitus

OBJECTIVE: To determine the effects of zinc (Zn) supplementation on oxidative stress in persons with type 2 diabetes mellitus (type 2 DM). DESIGN: Tunisian adult subjects with HbA1c >7.5% were supplemented for six months with 30 mg/day of Zn as Zn gluconate or placebo. The effects of supplementation on plasma zinc (Zn), copper (Cu), urinary Zn, plasma thiobarbituric acid reactive substances (TBARS), Cu-Zn superoxide dismutase (SOD) and glutathione peroxidase activities (GPX) in red blood cells, blood lipids and lipoproteins, HbA1c and fasting glucose were measured at the beginning of the study and after three and six months. RESULTS: At the beginning of the study, more than 30% of the subjects exhibited plasma Zn values less than the normal minimum of 10.7 micro mol/L, whereas levels of plasma Cu and antioxidant RBC Cu-Zn SOD and GPx enzyme activities were in the normal ranges. Oxidative stress, monitored by plasma TBARS, was increased in individuals with diabetes compared with healthy Tunisian subjects (3.32 +/- 0.05 micro mol/L vs. 2.08 +/- 0.04 micro mol/L) and an inverse correlation was found between Zn plasma levels and plasma TBARS. After three and six months of Zn supplementation, all of the subjects exhibited plasma Zn values greater than 10.7 micro mol/L. There was a decrease of plasma TBARS in Zn supplemented group after six months (15%) with no significant changes in the placebo group. Supplementation did not alter significantly HbA1c nor glucose homeostasis. No adverse effects of Zn supplementation were observed on Cu status or HDL cholesterol. CONCLUSIONS: These data suggest the potential beneficial antioxidant effects of Zn supplementation in persons with type 2 DM. These results are particularly important in light of the deleterious consequences of oxidative stress in persons with diabetes.     

Eucommia ulmoides Oliver leaf extract increases endogenous antioxidant activity in type 2 diabetic mice

Eucommia ulmoides Oliver (Du-zhong) leaf extract was investigated for its antioxidant effects in type 2 diabetic animals, C57BL/KsJ-db/db mice. Du-zhong extract equivalent to 1% dried whole Du-zhong leaf (0.187 g of extract/100 g of diet) was added to the experimental diets for 6 weeks. The Du-zhong extract supplement significantly lowered blood glucose concentrations and elevated plasma paraoxonase activity compared with the control group. The activities of erythrocyte superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) were significantly higher in the Du-zhong group compared with the control group, while glutathione reductase (GR) activity was not different between groups. The activities of SOD, GSH-Px, and GR in liver and kidney were not affected by Du-zhong extract supplementation, whereas the CAT activity was significantly higher in the Du-zhong group than in the control group. Du-zhong extract supplementation resulted in lower levels of hydrogen peroxide and lipid peroxide in erythrocytes, liver, and kidney. These results suggest that the antioxidant activity of Du-zhong extract is potentially beneficial for the prevention and management of complications of type 2 diabetes.     

Short-Term Calorie Restriction Maintains Plasma Insulin Concentrations along with a Reduction in Hepatic Insulin-Degrading Enzyme Levels in db/db Mice

Maintaining blood insulin levels is important for patients with diabetes because insulin secretion capacity declines with the development of the disease. Calorie restriction (CR) is effective for the improvement of glucose tolerance, but it is not clear whether CR can maintain insulin levels in the late stage of diabetes. We examined the effect of CR on whole-body glucose tolerance and fasting blood insulin concentrations in the late stage of diabetes. Male db/db mice were subjected to either a standard laboratory diet ad libitum for 3 weeks (dbdb group) or 40% CR (dbdb+CR group). CR significantly decreased body mass and epididymal fat weight. Glucose tolerance and fasting glucose levels were significantly improved with 3-week CR. Fasting insulin concentrations were decreased in the dbdb group but were maintained in the dbdb+CR group. CR significantly reduced insulin-degrading enzyme (IDE) levels in the liver, and hepatic IDE levels were significantly positively and negatively correlated with plasma glucose concentrations (area under the curve) after glucose administration and after fasting insulin concentrations, respectively. Therefore, 3-week CR maintained blood insulin levels and improved glucose tolerance with decreased hepatic IDE levels in an animal model of late-stage diabetes.     

Interactions between vitamins C and E in human subjects

Despite convincing in vitro evidence, a vitamin C-E interaction has not been confirmed in vivo. This study was designed to examine the effects of supplementation with either vitamin C or E on their respective plasma concentrations, other antioxidants, lipids and some haemostatic variables. Fasting blood was collected before and after intervention from thirty healthy adults in a double-blinded crossover study. Baselines for measured variables were established after 2 weeks of placebo supplementation, followed by daily supplementation with 73.5 mg RRR-alpha-tocopherol acetate or 500 mg ascorbic acid, and placebo, for 6 weeks. A 2 month washout preceded supplement crossover. Mean values showed that plasma lipid standardised alpha-tocopherol increased with ascorbic acid supplementation: from 4.09 (sem 0.51) to 4.53 (sem 0.66) micromol/mmol total cholesterol plus triacylglycerol (P < 0.05), and plasma ascorbic acid increased from 62.8 (sem 14.9) to 101.3 (sem 22. 2) micromol/l (P < 0.005). Supplementation with (RRR)-alpha-tocopherol acetate increased plasma alpha-tocopherol from 26.8 (sem 3.9) to 32.2 (sem 3.8) micromol/l (P < 0.05), and lipid-standardised alpha-tocopherol from 4.12 (sem 0.48) to 5.38 (sem 0.52) micromol/mmol (P < 0.001). Mean plasma ascorbic acid also increased with vitamin E supplementation, from 64.4 (sem 13.3) to 76. 4 (sem 18.4) micromol/l (P < 0.05). Plasma ferric reducing (antioxidant) power and glutathione peroxidase (U/g haemoglobin) increased in both groups, while urate, total cholesterol and triacylglycerol levels decreased (P < 0.05 throughout). Results are supportive of an in vivo interaction between vitamins C and E.     

胰岛素泵在2型糖尿病并肺部感染的应用效果观察

目的观察应用胰岛素泵进行连续皮下胰岛素输注(CSII)治疗2型糖尿病并肺部感染患者强化血糖控制的疗效。方法将住院的2型糖尿病并肺部感染患者83例随机分为皮下胰岛素泵治疗组(CSII组,42例)和多次皮下注射治疗组(MSII组,41例),观察血糖、血糖下降至正常的时间、肺部感染控制时间、费用及低血糖发生率。结果两组患者的血糖治疗后均明显下降,达目标血糖值的时间、肺部感染控制时间、胰岛素用量、低血糖发生率CSII组较MSII组明显减少(P<0.05);CSII组治疗后糖化血红蛋白、总胆固醇、C-反应蛋白明显降低,而空腹C肽、高密度脂蛋白-胆固醇明显升高(P<0.05)。而MSII组治疗前后上述指标的差异无统计学意义(P>0.05)。结论CSII能更好地控制血糖,纠正代谢紊乱,减少费用和住院天数,并能减少低血糖发生,是较为理想的方法。     

Comparison of the antioxidant effects of Concord grape juice flavonoids alpha-tocopherol on markers of oxidative stress in healthy adults

BACKGROUND: Concord grape juice (CGJ) is a rich source of flavonoids, which have greater antioxidant efficacy in vitro than does alpha-tocopherol; however, the efficacies of flavonoids and alpha-tocopherol in vivo have not been compared. OBJECTIVE: We compared the in vivo antioxidant efficacy of CGJ with that of alpha-tocopherol in healthy adults. DESIGN: Subjects were randomly assigned to receive either 400 IU RRR-alpha-tocopherol/d (n = 17) or 10 mL CGJ. kg(-1). d(-1) (n = 15) for 2 wk. Serum oxygen radical absorbance capacity, plasma protein carbonyls, urinary F(2)-isoprostanes, and resistance of LDL to ex vivo oxidation were measured before and after supplementation as markers of antioxidant status and oxidative stress. RESULTS: After supplementation, plasma alpha-tocopherol increased 92% in subjects who received alpha-tocopherol (P < 0.001); plasma total and conjugated phenols increased 17% (P < 0.01) and 22% (P < 0.001), respectively, in subjects who received CGJ. There was a significant change in plasma triacylglycerols in both groups, but the concentrations were within the normal range. CGJ supplementation was associated with significantly higher triacylglycerols than was alpha-tocopherol supplementation. Both supplementation regimens significantly increased serum oxygen radical absorbance capacity (P < 0.001) and LDL lag time (P < 0.001) and significantly decreased the LDL oxidation rate (P < 0.01), with no significant difference in effectiveness. Protein carbonyl concentrations in native plasma decreased 20% after CGJ supplementation, which was a significantly different response than that after alpha-tocopherol supplementation (P < 0.05). CONCLUSIONS: In healthy adults, 10 mL CGJ. kg(-1). d(-1) increased serum antioxidant capacity and protected LDL against oxidation to an extent similar to that obtained with 400 IU alpha-tocopherol/d but decreased native plasma protein oxidation significantly more than did alpha-tocopherol. CGJ flavonoids are potent antioxidants that may protect against oxidative stress and reduce the risk of free radical damage and chronic diseases.     

胰岛素强化治疗新诊断2型糖尿病患者成本-效果分析

目的 分析3种胰岛素强化治疗方案的成本-效果,为选择临床治疗方案提供参考。方法 对新诊断2型糖尿病患者随机分为3组。A组仅给予持续皮下注射胰岛素（CSII）,B组给予CSII联合二甲双胍和吡格列酮,C组给予CSII联合西格列汀。收集治疗前后的空腹血糖（FPG）、餐后2 h血糖（2hPG）、血糖达标时间、住院天数、低血糖发生次数及成本,比较3种方案的成本-效果。结果 各组患者经治疗后FPG、2hPG均下降（均P<0.01）,3组的血糖达标时间、住院天数及低血糖发生次数差异均有统计学意义（均P<0.01）。A、B、C组有效率的成本-效果比分别为139.37、134.29、135.66。以A组为对照,B组和C组的增量成本-效果比分别为25.52、53.85。敏感性分析支持基础分析结果。结论 CSII联合二甲双胍和吡格列酮治疗新诊断2型糖尿病患者是最经济、有效的方案;对于低血糖发生危险性高的患者,可选CSII联合西格列汀。     

Supplementation of coenzyme Q10 and α-tocopherol lowers glycated hemoglobin level and lipid peroxidation in pancreas of diabetic rats

The importance of nutritional supplementation in diabetes remains an unresolved issue. The present study was undertaken to examine the effects of α-tocopherol and CoQ₁₀, powerful antioxidants, on metabolic control and on the pancreatic mitochondria of GK rats, a model of type 2 diabetes. We also evaluated the efficacy of these nutrients in preventing the diabetic pancreatic lesions observed in GK rats. Rats were divided into 4 groups, a control group of diabetic GK rats and 3 groups of GK rats administered with α-tocopherol and CoQ₁₀ alone or both in association, during 8 weeks. Fasting blood glucose levels were not significantly different between the groups, nor were blood glucose levels at 2 hours after a glucose load. HbA1c level was significantly reduced in the group supplemented with both antioxidants. Diabetes induced a decrease in coenzyme Q plasma levels that prevailed after treatment with antioxidants. In addition, the plasma α-tocopherol levels were higher after treatment with the antioxidants. An increment in some components of the antioxidant defense system was observed in pancreatic mitochondria of treated GK rats. Moreover, the antioxidants tested either alone or in association failed to prevent the pancreatic lesions in this animal model of type 2 diabetes. In conclusion, our results indicate that CoQ₁₀ and α-tocopherol decrease glycated HbA1c and pancreatic lipid peroxidation. These antioxidants increase some components of the antioxidant defense system but do not prevent pancreatic lesions. Thus, we cannot rule out the potential benefit of antioxidant treatments in type 2 diabetes in the prevention of their complications.     

黄连素联合二甲双胍治疗2型糖尿病合并非酒精性脂肪肝的临床观察

目的 观察黄连素联合二甲双胍治疗2型糖尿病合并非酒精性脂肪肝的疗效及安全性.方法 选择初诊2型糖尿病合并非酒精性脂肪患者78例,治疗组(黄连素+二甲双胍)38例和对照组(二甲双胍)40例.治疗前后测定体重指数(BMI)、FPG、2hPG、HbA1c、FINS,血脂(TC、TG、HDL-C、LDL-C),肝功能(AST、ALT、GGT),计算胰岛素抵抗指数(HOMA-IR).观察期16周.结果 与对照组相比,治疗组可进一步降低血糖、减轻体重、增加胰岛素敏感性(P＜ 0.05);治疗组的血脂、肝功能的改善明显优于对照组(P＜0.01).结论 黄连素联合二甲双胍治疗2型糖尿病合并NAFLD具有一定的疗效.