A mixture of Salacia reticulata (Kotala himbutu) aqueous extract and cyclodextrin reduces body weight gain,visceral fat accumulation,and total cholesterol and insulin increases in male Wistar fatty rats

This study examined the effects of a mixture of an aqueous extract of Salacia reticulata (Kotala himbutu) and cyclodextrin (SRCD) on various metabolic parameters and cecal fermentation in obese fa/fa male Wistar fatty rats, a model of type 2 diabetes mellitus. Wistar fatty rats were fed 0% (control group) or 0.2% SRCD-supplemented diets and weighed weekly. The plasma glucose, triacylglycerol, total cholesterol, insulin, and adiponectin concentrations were measured at weeks 0, 2, 4, and 5. SRCD supplementation suppressed the time-dependent increase in the plasma total cholesterol and insulin concentrations. After 6 weeks of a 0.2% SRCD-supplemented diet, the body weight gain, food intake, visceral fat mass, liver mass, and liver triacylglycerol content of the rats were significantly lower, whereas the plasma adiponectin concentrations were significantly higher than those of the control group. SRCD supplementation had no significant effect on plasma glucose and triacylglycerol concentrations. SRCD supplementation significantly increased cecum mass, whereas it significantly decreased the cecal butyrate and short-chain fatty acid (sum of the acetate, butyrate, and propionate) concentrations. All of the rats were subjected to an oral glucose tolerance test at the beginning of week 6. The area under the curve for insulin was significantly smaller with SRCD supplementation and showed no change in glucose tolerance compared to that of the control group. These results suggest that bioactive compounds in SRCD may suppress the development of type 2 diabetes mellitus by influencing glucose and lipid metabolism in male Wistar fatty rats and that SRCD may influence cecal fermentation.     

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.     

Glucose kinetics in protein depletion--effect of glucose infusion in the fasted rat

A primed constant infusion of [6-3H]glucose was used to determine glucose turnover in rats fasted for 48 h that had previously been pair-fed isoenergetic 4% and 14.4% protein diets for 6 wk. The protein-depleted rats had a low body weight and lower plasma glucose and plasma insulin concentrations compared with the 14.4% protein pair-fed control animals. The rate of appearance of glucose in plasma in the protein-depleted rats was significantly less than that in the pair-fed controls. During an intravenous infusion of unlabeled glucose (38.8 mumol.kg-1.min-1) plasma glucose concentrations and glucose appearance increased in both groups. Plasma insulin concentration remained lower in the 4% protein-fed group though the percentage of increase above basal was similar in both groups during glucose infusion. The clearance of glucose from the blood and suppression of endogenous glucose production during the exogenous glucose infusion were similar in both control and protein-depleted rats. Rats fed a 14.4% protein diet ad libitum consumed more diet than the pair-fed groups and their body weights were greater. However, fasting plasma glucose and insulin, concentrations were similar to the 14.4% protein pair-fed animals. This indicates that the observed changes in glucose metabolism in the 4% protein-fed animals were due to a reduced dietary ratio of protein to carbohydrate rather than reduced energy intake.     

初断乳大鼠锌补充对成年高脂诱导肥胖后胰岛素的影响

目的 探讨初断乳大鼠锌补充对成年期高脂饮食下胰岛素水平的影响,为阐明生命早期适量补锌预防成年后胰岛素抵抗的机制提供重要依据。方法 初断乳雄性SD大鼠85只随机分为基础饲料组和高、中、低锌补充组。锌补充4周后各组均以基础饲料喂养1周,于第5周末检测大鼠血糖、胰岛素水平并计算胰岛素抵抗指数。随后将基础饲料组大鼠随机分为肥胖组和正常对照组,肥胖诱导组及3个锌补充组均喂以高脂饲料。高脂干预8周后处死所有大鼠并检测上述指标。结果 大鼠成年高脂干预后,1)3个锌补充组分别较肥胖诱导组体重明显降低(P＜0.05),高脂饲料喂养后锌补充组体重正常,而肥胖诱导组发生肥胖;2)3个锌补充组分别较肥胖诱导组血糖、胰岛素明显降低(P＜0.05),而胰岛素抵抗指数明显升高(P＜0.05),高脂饲料喂养后锌补充组胰岛素水平正常,而肥胖诱导组产生胰岛素抵抗。结论 生命早期适量补锌可持续发挥作用,在一定程度上维持成年后高脂膳食下血糖和胰岛素处于正常水平,预防胰岛素抵抗发生。     

Molasses increases HDL cholesterol in rats research note

Two experiments were conducted to determine whether molasses might exert effects on serum lipoproteins. In experiment 1, 24 rats were divided into two groups and fed diets containing liquid molasses from sugar beet or sucrose (7.71 g of molasses dry matter or sucrose per kg of diet). The second experiment included four groups of rats (n = l2/group) and was conducted in a bifactorial design, with the factors being molasses (non-supplementation vs. supplementation of 77.1 g of molasses dry matter per kg of diet at the expense of sucrose) and dietary cholesterol (0 vs. 5 g/kg diet). In experiment 1, the ratio of low-density lipoprotein (LDL) to high-density lipoprotein (HDL) cholesterol concentration tended to be lower in rats fed the molasses diet than in rats fed the control diet (p < 0.15). In experiment 2, rats fed the molasses diet had higher concentrations of HDL cholesterol (+ 26%) than control rats fed diets without molasses (p < 0.05). This effect was independent of the dietary cholesterol concentration. Concentrations of cholesterol in LDL, very low-density lipoprotein (VLDL), and liver as well as concentrations of triacylglycerols in plasma and liver remained unaffected by molasses in both experiments. In conclusion, the results of this study suggest that supplementation of molasses is effective at raising HDL cholesterol levels in rats.     

Antioxidant effect of saponin: potential action of a soybean flavonoid on glucose tolerance and risk factors for atherosclerosis

At the present time, much attention is being paid to antioxidant substances because many pathological conditions are associated with oxidative stress. The purpose of the present study was to discover the potency of saponin (2-phenyl-benzopyrane), a soybean flavonoid, with respect to its hypoglycaemic and hypolipidaemic action, and the association of these effects with oxidative stress. Male Wistar rats were divided into two groups (n = 6): control group and saponin-treated group (60 mg/kg) during 30 days. Saponin had no effects on glucose tolerance. Although no changes had been observed in low-density lipoprotein-cholesterol, saponin-treated animals had increased low-density lipoprotein-cholesterol/triacylglycerol ratio and decreased triacylglycerol, very low-density lipoprotein-cholesterol and total/high-density lipoprotein-cholesterol ratio than the control group. Saponin-treated rats showed lower lipid hydroperoxide than control rats, indicating decreased potential to atherosclerosis. No alterations were observed in antioxidant enzymes, superoxide dismutase and glutathione peroxidase, while lipid hydroperoxide were decreased in saponin-treated rats. In conclusion, the beneficial effects of saponin on serum lipids were related to a direct saponin antioxidant activity.     

Dietary bitter melon seed increases peroxisome proliferator-activated receptor-γ gene expression in adipose tissue, down-regulates the nuclear factor-κB expression, and alleviates the symptoms associated with metabolic syndrome

The objective of this study was to examine the extent to which bitter melon seed (BMS) alleviates the symptoms associated with metabolic syndrome and elucidate the mechanism by which BMS exerts beneficial effects. Three-month-old female Zucker rats were assigned to following groups: lean control (L-Ctrl), obese control (O-Ctrl), and obese + BMS (O-BMS). The control groups were fed AIN-93M purified rodent diet, and the O-BMS group was fed AIN-93M diet modified to contain 3.0% (wt/wt) ground BMS for 100 days. After 100 days of treatment, BMS supplementation in the obese rats lowered the total serum cholesterol by 38% and low-density lipoprotein-cholesterol levels by about 52% and increased the ratio of serum high-density lipoprotein-cholesterol to total cholesterol compared to the O-Ctrl group. The percentage of total liver lipids was about 32% lower and serum triglyceride levels were 71% higher in the O-BMS group compared to the O-Ctrl group. Serum glucose levels were significantly lowered partly because of the increase in the serum insulin levels in the BMS-based diet groups. BMS supplementation increased the expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) in the white adipose tissue of the obese rats significantly (P?相似文献   

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).     

Magnesium deficiency modulates the insulin signaling pathway in liver but not muscle of rats

Altered insulin secretion and sensitivity have been observed in Mg-deficient animals. However, the effects of Mg deficiency and supplementation on intracellular signaling events triggered by insulin are unknown. Therefore, we studied the early steps of insulin action in muscle and liver of rats fed Mg-deficient (DF-6, DF-11) or control (CO-6, CO-11) diets for 6 or 11 wk, respectively, and Mg-deficient or control diets for 6 wk, followed by Mg supplementation for 5 wk (SDF and SCO groups, respectively). There were no differences in the glucose disappearance rate (K(itt)) or insulin signaling between CO-6 and DF-6 rats. Between the two groups of rats fed for 11 wk, the DF-11 group had a significantly greater K(itt). SDF and SCO rats had K(itt) that did not differ from CO-11 rats, but that were significantly lower than in DF-11 rats. In the latter rats, insulin receptor and insulin receptor substrate-1 protein and phosphorylation levels were elevated in liver and there was a greater association between the insulin receptor substrate-1 and p85 subunit of phosphatidyl-inositol 3-kinase compared with CO-11 rats. There were no differences in the early steps of insulin action in SDF and control rats. These results suggest that the normal insulin sensitivity maintained by Mg supplementation and the increased insulin sensitivity produced by a long period of Mg deprivation may result, at least in part, from alterations in or maintenance of the early molecular steps of insulin action in hepatic tissue.     

Hypoglycemic effect of Chlorella vulgaris intake in type 2 diabetic Goto-Kakizaki and normal Wistar rats

The aim of this study was to examine the hypoglycemic effect of chlorella in 6 week-old type 2 diabetic Goto-Kakizaki (GK, n=30) rats and 6 week-old normal Wistar (n=30) rats. Animals were randomly assigned to 3 groups respectively, and were fed three different experimental diets containing 0%, 3% or 5% (w/w) chlorella for 8 weeks. In diabetic GK rats, the insulinogenic-indices were not significantly different among the groups. The concentrations of fasting plasma glucagon and hepatic triglyceride, and the insulin/glucagon ratios of the GK-3% chlorella and GK-5% chlorella groups were significantly lower than those of the GK-control group. The HOMA-index and the concentrations of fasting blood glucose and plasma insulin of the GK-3% chlorella and GK-5% chlorella groups were slightly lower than those of the GK-control group. In normal Wistar rats, the insulinogenic-indices were not significantly different among the normal groups, but that of the Wistar-5% chlorella group was slightly higher than the other groups. The concentrations of fasting blood glucose and plasma insulin, and the HOMA-index of the Wistar-5% chlorella group were a little higher, and the fasting plasma glucagon concentration and the insulin/glucagon ratio of the Wistar-5% chlorella group were significantly higher than those of the Wistar-control and Wistar-3% chlorella groups. In conclusion, this study shows that the glucose-stimulated insulin secretion was not affected by the intake of chlorella, which could be beneficial, however, in improving insulin sensitivity in type 2 diabetic GK and normal Wistar rats.     

锌对热暴露大鼠血浆与肝、肾上腺中锌、铜、铁含量的影响

目的：　测定热暴露大鼠血浆、肝、肾上腺 Ｚｎ 、 Ｃｕ 、 Ｆｅ 含量以探讨锌对热暴露动物某些微量元素的影响。方法：　４８ 只７ ～８ 周龄雄性 Ｓ Ｄ 大鼠随机等分为高锌（ Ｈ Ｚ） 、中锌（ Ｍ Ｚ） 和低锌（ Ｌ Ｚ） 三组。每组大鼠再等分为两部分,一部分用于高温暴露,另一部分用于室温对照。每公斤高、中、低锌饲料锌含量测定值（ ｍ ｇ） 分别为９２ ．２ 、４５ ．６ 、２１ ．７ 。三组大鼠在室温下预饲相应饲料１４ｄ 后,将高温暴露大鼠转入高温室（ Ｔｄ Ｂ４０ ．５ ℃, Ｔｗ ｂ３０ ．８ ℃） 连续暴露３ｈ 后,即刻断头取样。用 Ａ Ａ Ｓ 火焰法测定样品中 Ｚｎ 、 Ｃｕ 、 Ｆｅ 含量。结果：　（１） 与室温对照值比,热暴露３ｈ 后,血浆 Ｚｎ 、 Ｆｅ 浓度下降, Ｃｕ 浓度升高,肝 Ｚｎ 和肾上腺 Ｃｕ 含量增加;（２） 在室温对照值之间, Ｈ Ｚ 组血浆锌浓度显著高于 Ｌ Ｚ 组;（３） 在热暴露值之间, Ｈ Ｚ 组肾上腺 Ｃｕ 含量显著或非常显著地高于 Ｍ Ｚ 组与 Ｌ Ｚ 组。结论：　（１） 补锌主要影响热应激大鼠体内微量元素 Ｚｎ与 Ｃｕ 的代谢或分布,而对 Ｆｅ 的影响较小;（２） 高锌（９２ ．２ ｍ ｇ／ｋｇ 饲料） 摄入可使热应激大鼠血浆 Ｚｎ 浓度升高、肾上腺     

Combined effects of exercise and soy isoflavone diet on paraoxonase, nitric oxide and aortic apoptosis in ovariectomized rats

Menopause is associated with an increased risk of cardiovascular disease (CVD). Exercise and soy isoflavone diets have been suggested to reduce the risk of CVD in postmenopausal women. We investigated the effects of exercise, or combined exercise and soy isoflavone diet, on plasma lipid profiles, paraoxonase (PON), nitric oxide (NO) and apoptosis in the aorta of ovariectomized (OVX) rats. Thirty-two female Sprague-Dawley rats were divided into four groups: OVX with general diet (OVX-GD), OVX with isoflavone diet (OVX-ISO), OVX-GD with exercise training (OVX-ET) and OVX-ISO with exercise training (OVX-ISO+ET). The experimental rats undertook treadmill training (30 min/day, 4 days/week) and/or were supplied a soy isoflavone diet (added to the experimental diet at 2.39 mg/g protein) for 12 weeks. Body weight and levels of total cholesterol (TC), triglyceride (TG), LDL-cholesterol (LDL-C) increased in the OVX rats and HDL-C decreased. These effects were reduced by exercise and/or soy isoflavone supplementation. PON and NO activities were higher in the OVX-ISO+ET group than in the OVX-GD group. In addition, this group had lower caspase-9 and -3 and higher Bcl-2 expression, and there was less aortic apoptotic cell death. These results suggest that a combination of exercise and a soy isoflavone diet has beneficial effects in terms of protecting against cardiovascular risk factors by controlling lipid profiles and the related enzyme, PON, as well as NO activity and apoptosis of the aorta in OVX rats.     

Sea tangle supplementation lowers blood glucose and supports antioxidant systems in streptozotocin-induced diabetic rats

Diabetes mellitus is a chronic disease associated with serious complications that may be linked to increased lipid peroxidation. This study investigated the effects of dietary supplementation of sea tangle on lipid peroxidation and antioxidant systems in streptozotocin (STZ)-induced diabetes. Forty Sprague-Dawley rats were divided into four groups (n = 10 each) fed AIN76-based diets with either sea tangle powder, water extract of sea tangle, or sodium alginate, or a control diet with no supplement. On day 21 after beginning the diets, rats received intramuscular injections of STZ (45 mg/kg of body weight) to induce diabetes. Experimental diet feeding was continued for 3 more weeks. Dietary supplementation with water extract of sea tangle resulted in lower plasma glucose compared with the control and sodium alginate groups. There was no significant difference in plasma and hepatic lipid peroxides among the groups. Sea tangle and sodium alginate did not affect activities of catalase and glutathione peroxidase; however, supplementation of water extract of sea tangle resulted in higher superoxide dismutase activity as compared with the control and sodium alginate groups. The plasma concentration of alpha-tocopherol increased in the sea tangle water extract group, but the hepatic concentration of alpha-tocopherol was not affected by dietary supplementation. Plasma retinol was not different among experimental groups. In conclusion, our results showed that water extract of sea tangle reduces plasma glucose and protects the antioxidant system in diabetic rats. These results suggest that water extract of sea tangle contains unknown physiologically active components, other than alginic acid, that may exert a protective effect against diabetes.     

Effects of alpha-tocopherol supplementation and continuous subcutaneous insulin infusion on oxidative stress in Korean patients with type 2 diabetes

BACKGROUND: Most Koreans with type 2 diabetes are insulin deficient and insulin resistant. Continuous subcutaneous insulin infusion (CSII) provides a suitable amount of insulin to overcome insulin deficiency and achieve near-normal blood glucose concentrations. Our previous study showed, however, that CSII does not reduce oxidative stress even though it normalizes blood glucose concentrations. OBJECTIVE: The purpose of this study was to determine whether CSII plus alpha-tocopherol supplementation for 2 mo would alter oxidative stress in Korean patients with type 2 diabetes. DESIGN: Ninety-eight subjects received CSII plus either 200 mg alpha-tocopherol/d (n = 48) or a placebo (n = 50) for 2 mo. The general characteristics (age, duration of diabetes, body mass index, and blood glucose concentrations) of the 2 groups were not significantly different. RESULTS: Fasting and postprandial blood glucose concentrations of all subjects were normalized after CSII. Fasting plasma insulin concentrations did not differ significantly between the 2 groups after CSII. Lipid peroxide concentrations in plasma and red blood cells decreased and alpha-tocopherol concentrations in plasma and red blood cells increased after alpha-tocopherol supplementation. However, these changes were not affected significantly by CSII. Plasma vitamin C concentrations increased significantly after CSII plus alpha-tocopherol supplementation. However, the activities of antioxidant enzymes in red blood cells did not change significantly after CSII plus alpha-tocopherol supplementation. CONCLUSION: alpha-Tocopherol supplementation was beneficial in decreasing blood lipid peroxide concentrations without altering antioxidant enzyme activities in Korean patients with type 2 diabetes treated with CSII.     

Effect of skim milk and dahi (yogurt) on blood glucose, insulin, and lipid profile in rats fed with high fructose diet

In the present study, the effect of skim milk and the fermented milk product named dahi (yogurt) on plasma glucose, insulin, and lipid levels as well as on liver glycogen and lipid contents in rats fed with high fructose diet has been investigated. Rats were fed with high fructose diet (21%) supplemented with skim milk, dahi (10 g/day each), or no milk product (control group) for 6 weeks. After 6 weeks of high fructose diet administration, the plasma glucose became significantly higher in control animals (246 mg/dL), whereas it was lower in skim milk (178 mg/dL)- and dahi (143 mg/dL)-fed rats. The glucose tolerance became impaired at the third week of feeding of high fructose diet in control animals, whereas in skim milk- and dahi-fed animals achievement of glucose intolerance was delayed until the fourth and fifth week, respectively. Blood glycosylated hemoglobin and plasma insulin were significantly lower in skim milk (10% and 34%, respectively)- and dahi (17%, and 48%, respectively)-fed animals than those of the control group. Plasma total cholesterol, triglycerides, low-density lipoprotein-cholesterol, and very-low-density lipoprotein-cholesterol and blood free fatty acids were significantly lower in skim milk (13%, 14%, 14%, 19%, and 14%, respectively)- and dahi (22%, 33%, 30%, 33%, and 29%, respectively)-fed animals as compared with control animals. Moreover, the total cholesterol, triglyceride, and glycogen contents in liver tissues were also lower in skim milk (55%, 50%, and 36%, respectively)- and dahi (64%, 27%, and 4%, respectively)-fed animals as compared with control animals. In contrast, high-density lipoprotein-cholesterol in plasma was higher in skim milk (14%)- and dahi (29%)-fed animals as compared with control animals. These results indicate that skim milk and its fermented milk product, dahi, delay the progression of fructose-induced diabetes and dyslipidemia in rats and that these may be useful as antidiabetic food supplements that can be included in daily meals of the diabetic as well as normal population.     

Supplementation of cheonggukjang and red ginseng cheonggukjang can improve plasma lipid profile and fasting blood glucose concentration in subjects with impaired fasting glucose

This study was conducted to investigate the plasma lipid profile and blood glucose-lowering effects of cheonggukjang (CH) and red ginseng CH (RGCH) in 45 subjects (men:women?=?27:18; mean age, 44.9?±?3.1 years) with impaired fasting glucose (IFG). Subjects were randomly divided into three groups: control (starch, 2?g/day), CH (20?g/day), and RGCH (20?g/day). Each volunteer received his or her daily doses for 8 weeks. The supplementation with CH and RGCH significantly decreased the plasma total cholesterol about 30.0?mg/mL and 37.7?mg/mL, respectively, compared to the initial value. The plasma low-density lipoprotein-cholesterol concentration was also significantly reduced by 29.66% and 23.42% in the CH and RGCH groups, respectively, compared to the initial value. The concentration of plasma non-high-density lipoprotein-cholesterol (107.9?mg/mL) was significantly lowered in the RGCH group compared to the initial value (139.1?mg/mL). The level of erythrocyte thiobarbituric acid-reactive substances was significantly lowered in the CH (6.5?nmol/mL) and RGCH (6.6?nmol/mL) groups compared to the initial value (7.9?nmol/mL and 8.0?nmol/mL, respectively). The ratio of apolipoprotein B and apolipoprotein A-1 concentrations (2.5) was significantly reduced in the CH group compared to the initial value (3.0). The concentration of fasting blood glucose (FBG) was significantly lower in the CH- and RGCH-supplemented groups compared to the initial value. These results suggest that CH and RGCH can lower the FBG concentration and improve the plasma lipid profile in subjects with IFG.     

Effects of herring roe on plasma lipid, glucose, insulin and adiponectin levels, and hepatic lipid contents in mice

We previously reported that lipids extracted from salted herring roe product (Kazunoko), which contains large amounts of cholesterol, phosphatidylcholine and n-3 polyunsaturated fatty acids (PUFAs) such as eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3), decreased plasma lipid and glucose concentrations in mice. The aim of this study was to evaluate the effects of Kazunoko containing large amounts of protein on lipid and glucose metabolism in mice. Male Crlj:CD-1 (ICR) mice were fed three experimental diets containing lyophilized Kazunoko for 12 wk. The experimental diets were as follows: without Kazunoko (control diet); 1% Kazunoko (1% Kazunoko diet); and 4% Kazunoko (4% Kazunoko diet). Plasma total cholesterol, phospholipid and glucose concentrations tended to be lower in the 1% and 4% Kazunoko diet groups than in the control diet group. There were significant differences in plasma glucose concentration between the control and 4% Kazunoko diet groups (p<0.05). Plasma adiponectin concentrations in mice fed the 4% Kazunoko diet were also significantly higher than in those fed the control diet (p<0.05), but there were no marked differences in plasma insulin concentration among the three dietary groups. Hepatic total cholesterol and phospholipid contents tended to be lower in the 4% Kazunoko diet group than in control diet group. Plasma and hepatic n-3/n-6 ratios in the 1% Kazunoko diet and 4% Kazunoko diet groups were significantly higher when compared with those of the control diet group (p<0.005 and p<0.0005, respectively). These results suggest that ingestion of Kazunoko influences lipid and glucose metabolism in mice fed the Kazunoko diets, as compared with animals fed the control diet.     

Effects of xylitol as a sugar substitute on diabetes-related parameters in nondiabetic rats

Abstract The present study was examined the effects of xylitol feeding on diabetes-associated parameters in nondiabetic rats. Seven-week-old male Sprague-Dawley rats were randomly divided into three groups: control (five rats), sucrose (six rats), and xylitol (six rats). Animal had free access to a commercial rat pellet diet, and ad libitum water, 10% sucrose solution, and 10% xylitol solution were supplied to the control, sucrose, and xylitol groups, respectively. After 3 weeks of feeding of experimental diets, food intakes were significantly (P<.05) lower in the sucrose and xylitol groups compared with the control group. Drink intake was significantly higher in the sucrose group but significantly lower in the xylitol group compared with the control group. Body weight gain was significantly lower in the xylitol group compared with the sucrose group. Weekly nonfasting blood glucose was significantly increased, but fasting blood glucose was significantly decreased, in the sucrose group compared with the control and xylitol groups. Significantly better glucose tolerance was observed in the xylitol group compared with the control and sucrose groups. Serum insulin and fructosamine concentrations were not significantly influenced by the feeding of xylitol or sucrose. Relative liver weight and liver glycogen were significantly increased in the xylitol group compared with the sucrose group, whereas no difference was observed between the xylitol and control groups. Serum total cholesterol and low-density lipoprotein-cholesterol were significantly decreased in the sucrose and xylitol groups, and serum triglyceride of the xylitol group, but not the sucrose group, was significantly increased compared with the control group. Data of this study suggest that xylitol can be a better sweetener than sucrose to maintain diabetes-related parameters at a physiologically safer and stable condition.     

Consumption of a high-fat diet containing lard during the growth period in rats predisposes them to favorably respond to the diet in later life

To investigate whether preferential fat intake by adult rats could be linked to fat-feeding of rats during the growth period, this paper describes the next two studies. Three groups of 4-wk-old male rats in study 1 received one of three diets: control diet (CTD), low-fat high-carbohydrate diet (LFD), and high-fat low-carbohydrate diet (HFD). After 6 wk (dietary treatment period), 6 rats in each of the groups were sacrificed and the remaining rats were placed on a self-selection regimen of fat-protein diet (FPD) and carbohydrate-protein diet (CPD) for 3 wk (self-selection period). After the dietary treatment period, liver weight and plasma insulin concentration of the LFD group and perirenal fat tissue weight and plasma triacylglycerol and leptin concentrations of the HFD group were higher than those of the CTD group. Although no significant difference in fat energy ratio (F ratio) of combination diets self-selected by the three groups was observed, the F ratios of the combination diets were higher than that of the CTD. After the self-selection period, liver weight and plasma insulin concentration of the LFD group and plasma triacylglycerol concentrations of the HFD group decreased. These data suggested that the dietary selection pattern of the rats was associated with a reduced basal plasma insulin concentration. Three groups of rats in study 2 were placed on a self-selection regimen of the LFD and the HFD after being fed one of three diets (LFD, CTD and HFD) for 6 wk. Although the F ratio of the combination diet consumed by the CTD and the LFD groups was similar to that of the combination diet consumed by rats in study 1, the F ratio of the combination diet consumed by the HFD group was higher than that of other groups. These findings suggest that consumption of the fatty food during the growth period predisposed them to favorably respond to the diet that had become familiar to them in later life.     

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.