Elucidation of the effects of a high fat diet on trace elements in rabbit tissues using atomic absorption spectroscopy

Background  

The mechanism of atherogenesis is not yet fully understood despite intense study in this area. The effects of high fat diet (HFD) on the changes of trace elements [iron (Fe), copper (Cu) and zinc (Zn)] in several tissues of rabbits have not been documented before. Thus, the aim of this study was to elucidate the changes in trace elements in several tissues of rabbits fed on HFD for a period of feeding of 10 weeks.     

Differential Development of Glucose Intolerance and Pancreatic Islet Adaptation in Multiple Diet Induced Obesity Models

Background: The C57BL/6 mouse fed a high fat diet is a common and valuable model in experimental studies of obesity and type 2 diabetes (T2D). Different high fat diets are used and in order to determine which diet produces a model most accurately resembling human T2D, they need to be compared head-to-head. Methods: Four different diets, the 60% high fat diet (HFD) and the 58% high fat-high sucrose Surwit diet (HFHS) and their respective controls, were compared in C57BL/6J mice using glucose tolerance tests (IVGTT) and the euglycemic clamp. Results: Mice fed a HFD gained more weight than HFHS fed mice despite having similar energy intake. Both high fat diet models were glucose intolerant after eight weeks. Mice fed the HFD had elevated basal insulin, which was not seen in the HFHS group. The acute insulin response (AIR) was unchanged in the HFD group, but slightly increased in the HFHS diet group. The HFHS diet group had a threefold greater total insulin secretion during the IVGTT compared to its control, while no differences were seen in the HFD group. Insulin sensitivity was decreased fourfold in the HFD group, but not in the HFHS diet group. Conclusion: The HFD and HFHS diet models show differential effects on the development of insulin resistance and beta cell adaptation. These discrepancies are important to acknowledge in order to select the appropriate diet for specific studies.     

Baccaurea angulata fruit juice ameliorates altered hematological and biochemical biomarkers in diet-induced hypercholesterolemic rabbits

Hypercholesterolemia is an important risk factor linked to the alteration of blood hematology and clinical chemistry associated with the development and progression of atherosclerosis. Previous studies have demonstrated the safety and potential health benefits of Baccaurea angulata (BA) fruit. We hypothesized that the oral administration of BA fruit juice could ameliorate the alteration in the hematological and biochemical biomarkers of diet-induced hypercholesterolemic rabbits. The aim of this study was to investigate the effects of different doses of BA juice on the hematological and biochemical biomarkers in normo- and hypercholesterolemic rabbits. Thirty-five healthy adult New Zealand White rabbits were assigned to seven different groups for 90 days of diet intervention. Four atherogenic groups were fed a 1% cholesterol diet and 0, 0.5, 1.0, and 1.5 mL of BA juice per kg of rabbit daily. The other three normal groups were fed a commercial rabbit pellet diet and 0, 0.5, and 1.0 mL of BA juice per kg of rabbit daily. Baseline and final blood samples after 90 days of repeated administration BA juice were analyzed for hematological parameters while serum, aortic and hepatic lysates were analyzed for lipid profiles and other biochemical biomarkers. The alteration of the hemopoietic system, physiological changes in serum and tissues lipid profiles and other biochemicals resulting from the consumption of a high-cholesterol diet were significantly (P < .05) ameliorated by the administration of BA juice. Improvements of the biomarkers in rabbits were dose-dependent, markedly enhanced at the highest dose of juice (1.5 mL/kg/day). The results suggest potential health benefits of the antioxidant-rich BA fruit juice against hypercholesterolemia-associated hematological and biochemical alterations in the rabbit.     

The effects of Momordica charantia on obesity and lipid profiles of mice fed a high-fat diet

BACKGROUND/OBJECTIVES

The present study was conducted to investigate the effects of dried Momordica charantia aqueous extracts (MCA) and ethanol extracts (MCE) on obesity and lipid profiles in mice fed a high-fat diet.

MATERIALS/METHODS

Forty two ICR mice were randomly divided into six groups. The normal group was fed a basal diet, and other groups were fed a 45% high-fat diet (HFD) for 7 weeks. The normal and HFD groups were also orally administered distilled water each day for 7 weeks. The remaining groups received Momordica charantia extract (0.5 or 1.0 g/kg/day MCA, and 0.5 or 1.0 g/kg/day MCE). In order to measure the anti-obesity and lipid profile improvement effects, body and visceral tissue weight, lipid profiles, plasma insulin levels, hepatic malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured.

RESULTS

Both MCA and MCE significantly decreased body and visceral tissue weight relative to those of the HFD group (P < 0.05). Additionally high doses of MCE and MCA significantly reduced the plasmatic insulin levels compared to the HFD groups (P < 0.05) to concentrations comparable to those found in the normal group. MCA and MCE supplementation also significantly modulated the lipid profiles in plasma, liver, and feces compared to mice fed the HFD (P < 0.05). Furthermore MCA and MCE significantly increased hepatic SOD activity, and reduced MDA generation in the liver of the HFD mice (P < 0.05).

CONCLUSIONS

Results from the present study suggest that Momordica charantia extracts have anti-obesity effects and the ability to modulate lipid prolife of mice fed a HFD by suppressing body weight gain, visceral tissue weight, plasma and hepatic lipid concentrations, and lipid peroxidation along with increasing lipid metabolism.     

The effects of whey protein and chromium picolinate supplementation on visceral fat and metabolic status in high-fat-fed rats

The objective of this study was to evaluate the effects of whey protein (WP) and chromium picolinate (CrPic) on body composition and metabolic status in rats fed a high-fat diet (HFD). Male Wistar rats (n = 10/group, 8 weeks old) were divided into three groups. The control group was fed a HFD (300 g fat/kg diet). The other two groups were fed the HFD plus 320 g whey protein isolate/kg diet (HFD + WP) with or without 80 mcg CrPic/kg body wt/day (HFD + WP + CrPic). After six weeks, rats were fasted, blood samples were drawn, and visceral and subcutaneous fat pads were removed and weighed. Daily food intake was not affected by treatment. Rats fed HFD exhibited significant increases in body weight, body fat and metabolic risk factors (p ≤ 0.05). Rats fed the HFD + WP showed a significant decrease in body weight, serum glucose and blood lipids, and a significant increase in insulin levels (p ≤ 0.05). Rats fed the HFD + WP + CrPic had the lowest levels in total visceral fat, triglycerides, total cholesterol and free fatty acids, and the highest insulin levels (p ≤ 0.05). Tissue concentrations of chromium (Cr) increased with CrPic supplementation (p < 0.001). The results of this study support the use of WP and CrPic supplementation to improve body composition and metabolic syndrome risk factors.     

Supplementation of the black rice outer layer fraction to rabbits decreases atherosclerotic plaque formation and increases antioxidant status.

The influence of the supplementation of black and white rice outer layer fractions on atherosclerotic plaque formation induced by hypercholesterolemia was investigated in rabbits. Male rabbits (n = 32) were randomly divided into four groups. They were fed nonpurified diet (normal group), a lard (3.5 g/100 g) with high cholesterol (0.5 g/100 g) diet (HC group); the HC diet with 5 g/100 g white rice outer layer fraction (WRF group); or the HC diet with 5 g/100 g black rice outer layer fraction (BRF) for 2 mo. Blood samples were collected for determination of lipid concentration and oxidative and antioxidative status variables, and aortae were taken for the assessment of atherosclerotic plaques. The atherosclerotic plaque area in rabbits fed the BRF diet was 66% lower than that of the HC or WRF rabbits (P < 0.001). Supplementation of the black rice outer layer significantly (P < 0.05) lowered aortic 8-hydroxy-2'-deoxyguanosine (8-OHdG) (-52%, -44%) compared with the WRF or HC diets (P < 0.05). There were no differences in aortic 8-OHdG levels between rabbits fed the BRF and normal diets. The BRF diet significantly (P < 0.05) decreased the malondialdehyde (MDA) level of serum (-37%) and aortic artery (-50%) compared with the WRF diet. There were no differences in the concentrations of serum total cholesterol (TC), LDL cholesterol (LDL-C), HDL-C or the ratio of apoprotein (apo)I/apoB among the HC, WRF and BRF groups. Similarly, there were no differences in the serum vitamin E concentration and erythrocyte and aorta superoxide dismutase (SOD) activities among rabbits fed these diets. The serum concentration of most fatty acids except 18:1 did not differ between the WRF and the BRF groups. We conclude that the inhibition of atherosclerotic plaque formation derived from the black rice outer layer fraction in rabbits might be mediated by antioxidative or anti-inflammatory effects.     

A High-Fiber Diet or Dietary Supplementation of Acetate Attenuate Hyperoxia-Induced Acute Lung Injury

A high fiber diet (HFD) and dietary supplementation with acetate have been reported to have beneficial effects in a variety of diseases. We investigated the effects of a HFD and acetate supplementation on the gut microbiota and hyperoxia-induced acute lung injury (HALI) in mice. Mice were fed a control diet, HFD, or acetate supplementation for three weeks, and their gut microbiome composition, lung tissues, and bronchoalveolar lavage fluid (BALF) were examined after exposure to ambient air or hyperoxia. Both the HFD and acetate supplementation modified the gut microbiota community and increased the proportion of acetate-producing bacteria in mice exposed to hyperoxia. The HFD and acetate supplementation also increased the abundance of Bacteroides acidifaciens and reduced gut dysbiosis according to the ratio of Firmicutes to Bacteroidetes. Compared with hyperoxia-exposed mice fed a control diet, both the HFD and acetate supplementation significantly increased the survival time while reducing the severity of pulmonary edema and the concentrations of protein and inflammatory mediators in BALF. Moreover, the HFD and acetate supplementation reduced the production of free radicals, attenuated NF-κB signaling activation, and decreased apoptosis in the lung tissues. Overall, this study indicates that a HFD or acetate supplementation reduces the severity of HALI through alterations in the gut microbiota to exert anti-inflammatory effects.     

Caloric Restriction Prevents Metabolic Dysfunction and the Changes in Hypothalamic Neuropeptides Associated with Obesity Independently of Dietary Fat Content in Rats

Energy restriction is a first therapy in the treatment of obesity, but the underlying biological mechanisms have not been completely clarified. We analyzed the effects of restriction of high-fat diet (HFD) on weight loss, circulating gut hormone levels and expression of hypothalamic neuropeptides. Ten-week-old male Wistar rats (n = 40) were randomly distributed into four groups: two fed ad libitum a normal diet (ND) (N group) or a HFD (H group) and two subjected to a 25% caloric restriction of ND (NR group) or HFD (HR group) for 9 weeks. A 25% restriction of HFD over 9 weeks leads to a 36% weight loss with regard to the group fed HFD ad libitum accompanied by normal values in adiposity index and food efficiency ratio (FER). This restriction also carried the normalization of NPY, AgRP and POMC hypothalamic mRNA expression, without changes in CART. Caloric restriction did not succeed in improving glucose homeostasis but reduced HFD-induced hyperinsulinemia. In conclusion, 25% restriction of HFD reduced adiposity and improved metabolism in experimental obesity, without changes in glycemia. Restriction of the HFD triggered the normalization of hypothalamic NPY, AgRP and POMC expression, as well as ghrelin and leptin levels.     

Dietary supplementation with an extract of lycopene-rich tomatoes does not reduce atherosclerosis in Watanabe Heritable Hyperlipidemic rabbits

Tomatoes are rich in lycopene and other carotenoids which have shown beneficial effects on CVD in epidemiological and intervention studies. In the present study the effect of an extract of lycopene-rich tomatoes, Lyc-O-Mato on atherosclerosis was studies in Watanabe Heritable Hyperlipidemic rabbits. The rabbits were fed a control diet, a control diet supplemented with the tomato extract or a control diet supplemented with a mixture of plant oils for 16 weeks. Lycopene was detected only in plasma of rabbits receiving tomato extract. The tomato extract had no effect on cholesterol and triacylglycerol levels measured in total plasma, lipoprotein fractions and on aortic atherosclerosis evaluated biochemically and by microscopy. Oxidation of lipids in unfractionated plasma also was unaffected by the intake of tomato extract. In conclusion, the tomato extract increased plasma levels of lycopene in rabbits, but had no effect on hypercholesterolaemia, oxidation of plasma lipids or aortic atherosclerosis.     

Abietic acid has an anti-obesity effect in mice fed a high-fat diet

We investigated the anti-obesity effect of abietic acid in mice fed a high-fat diet with emphasis on changes in adipogenesis in epididymal adipose tissues. Male C57BL/6J mice were divided into four groups and fed a normal diet, a high-fat diet (HFD), or HFD plus oral administration of abietic acid (20 mg/kg of body weight/day [LA] or 40 mg/kg of body weight/day [HA]) for 8 weeks. Compared with the HFD group, mice orally administered 40 mg of abietic acid/kg of body weight/day exhibited significantly decreased body weight and adipose tissue weights. Serum triglyceride concentrations in the HA group were significantly lower than those in the HFD group, as were the levels of serum insulin and leptin. Hematoxylin and eosin staining revealed that epididymal adipose tissue mass was decreased by abietic acid administration. Abietic acid also inhibited the protein expression of sterol regulatory element-binding protein-1c, CCAAT/enhancer-binding protein α, and CD36 in epididymal adipose tissues, which are up-regulated by HFDs. These data demonstrate that abietic acid has an anti-obesity effect in mice mediated by the regulation of adipogenesis.     

Calcium deficiency-induced secondary hyperparathyroidism and osteopenia are rapidly reversible with calcium supplementation in growing rabbit pups

The reversibility of osteopenia secondary to isolated Ca deficiency (CaDef) is still not clear. We studied the effect of severe CaDef on Ca homeostasis and bone accrual in a 'hypercalcaemic' animal, the rabbit, during the post-weaning period and its reversibility on Ca supplementation. Male Belgian 5-week-old rabbit pups were fed CaDef diet (0.026 % Ca) for 10 weeks. As compared with those fed with a normal chow diet (0.45 % Ca), CaDef pups developed significant hypocalcaemia (P < 0.05), hypocalciuria (urinary Ca 76 (SEM 12) v. 17 (SEM 1) mg/l; P < 0.005), hypophosphataemia (serum inorganic P 100 (SEM 6) v. 65 (SEM 4) mg/l; P < 0.005), secondary hyperparathyroidism (SHPT) (serum intact parathyroid hormone human equivalent 18.2 (SEM 1.4) v. 125.0 (SEM 4.5) pg/ml; P < 0.001) and elevated serum calcitriol levels (34.0 (SEM 3.9) v. 91.0 (SEM 1.0) pg/ml; P < 0.005). Elevated urinary C-terminal telopeptide of class I collagen (P < 0.005) and total serum alkaline phosphatase (P < 0.005) suggested increased bone turnover. There was a significantly lower gain in bone mineral density (BMD) and bone mineral content (BMC) in the whole body and lumbar spine in vivo, and various sub-regions of the femur and tibia in vitro. Supplementation of adequate Ca (0.45 % Ca) after 15 weeks on the normal diet resulted in rapid catch-up growth, and resolution of SHPT. Rapid gain in various BMD and BMC parameters continued at 30 weeks of age, and both were comparable with those in rabbits on a normal diet. We conclude that Ca deficiency-induced SHPT and poor bone accrual in growing rabbit pups are rapidly reversible with Ca supplementation. The present study indicates that early intervention may be a more appropriate window period for human nutritional corrective measures.     

Effects of ingestion of collagen peptide on collagen fibrils and glycosaminoglycans in Achilles tendon

In order to investigate whether the oral ingestion of collagen peptide affects the extracellular matrix of tendon, two doses (0.2 g/kg and 1.0 g/kg body weight) were orally administered daily for 56 d to a rabbit, and both the size of collagen fibrils and the amount of glycosaminoglycans in the Achilles tendon were measured in comparison with those in a rabbit fed with a control protein, lactalbumin, or water alone. Ingestion of collagen peptide or lactalbumin induced a significant increase in collagen fibril diameter and a decrease in fibril density except for a high dose of lactalbumin compared with the water control. A histogram pattern of fibril diameter in a high dose of collagen peptide showed a peak at 160-180 nm, which was not observed in other groups. However the percentage of diameters over 200 nm was the lowest in this group but highest in the low-dose group of collagen peptide. The mean fibril diameter and mass average diameter of a high dose of collagen peptide were significantly smaller than those in a low dose. The amount of dermatan sulphate increased in the high-dose groups, while the amount of hyaluronic acid decreased in rabbits fed with collagen peptide or lactalbumin at either dose. These results suggest that the ingestion of collagen peptide affects the size of collagen fibrils and composition of glycosaminoglycans in the Achilles tendon and thus may improve the mechanical properties of the Achilles tendon.     

镁预防高脂膳家兔内皮细胞损伤的研究

目的：通过血浆血栓素（ＴＸＢ２）、６－酮前列腺素Ｆ１α（６－Ｋｅｔｏ－ＰＧＦ１α）、内皮素（ＥＴ）及一氧化氮（ＮＯ）等几个方面探讨镁预防高脂膳家兔诱发动脉粥样硬化形成的可能作用。方法：成年新西兰家兔随机分为正常对照组（基础饲料＋普通饮水）,高脂对照组（高脂饲料＋普通饮水）,高镁组（高脂饲料＋含镁４２．１ｍｇ／ｋｇ饮水）,观察１２周。结果：高脂对照组家兔血浆前列腺素Ｆ１α水平及ＮＯ含量下降,ＴＸＢ２及ＥＴ水平上升。补镁提高血浆６－Ｋｅｔｏ－ＰＧＦ１α浓度和ＮＯ含量,同时也可明显降低家兔血浆ＴＸＢ２、ＥＴ及ＴＸＢ２／６－Ｋｅｔｏ－ＰＧＦ１α比值。结论：镁有调节花生四烯酸代谢、保护内皮细胞及防治动脉粥样硬化形成的作用。     

A wax ester and astaxanthin-rich extract from the marine copepod Calanus finmarchicus attenuates atherogenesis in female apolipoprotein E-deficient mice

The aim of this study was to investigate the effect of dietary supplementation with an oil extracted from the zooplankton copepod Calanus finmarchicus [calanus oil (CO)] on atherosclerosis in apoE-deficient (apoE(-/-)) mice. Thirty 6-wk-old female apoE(-/-) mice (n = 10/group) were fed: 1) a Western-type, high-fat diet (HFD); 2) HFD supplemented with 1% (wt:wt) CO; or 3) HFD supplemented with 0.88% (wt:wt) corn oil + 0.12% (wt:wt) EPA+DHA ethyl esters (EPA+DHA) for 13 wk. Dietary CO supplementation lowered total aorta atherogenesis by 36.5% compared to the HFD (P < 0.01), whereas the reduction in the lesion prone aortic arch was 34.8% (P < 0.01). The degree of aortic atherogenesis was intermediate in mice fed EPA+DHA compared to those fed HFD and CO. The effect on atherogenesis was paralleled by reduced expression of hepatic genes for the proinflammatory cytokines, Ccl2, Icam1, Il1b, and Nfkb1, in mice fed CO compared to those fed HFD. For mice fed EPA+DHA, gene expression did not differ compared to those fed CO or HFD. Plasma concentrations of total cholesterol, TG, and cytokines did not differ between the groups at the end of the study. However, mice fed CO gained more weight compared to those fed HFD but not compared to those fed EPA+DHA. In conclusion, dietary CO supplementation attenuated atherosclerotic lesion formation in female apoE(-/-) mice and may be an effective and safe dietary intervention to reduce the development of atherosclerosis. However, further studies are warranted to elucidate the underlying physiological and molecular mechanisms.     

辛伐他汀和氨氯地平对实验性兔动脉粥样硬化进程中HO／CO系统的影响

目的探讨血红素加氧酶．一氧化碳系统在动脉粥样硬化中的变化、相互关系及辛伐他汀、氨氯地平对动脉粥样硬化进程中血红素加氧酶-一氧化碳的影响。方法家兔予以高胆固醇饮食（n=24）18周,8周后改用普通饮食并随机分为三组,模型组停用高胆固醇饮食,改普通饮食（n=8）;辛伐他汀组给予喂饲辛伐他汀进行药物干预8周,氨氯地平组给予喂饲氨氯地平进行药物干预8周（n=8）。同时设正常对照组（n=8）：给予普通饲料喂养16周。然后取静脉血分别用Chalmers A．H、硝酸还原酶法测定各实验组血中CO,取主动脉组织用免疫组织化学方法测定主动脉组织中HO-1的表达;并比较组间各项参数的差异。结果16周末模型组血脂水平、血浆一氧化碳水平、血红素加氧酶-1表达较对照组明显升高。辛伐他汀组血浆TC、TG、LDL下降明显,HDL升高;血浆一氧化碳水平及血红素加氧酶-1表达均明显降低。而氨氯地平组血脂无明显变化;血浆一氧化碳水平、血红素加氧酶-1表达亦明显降低。结论动脉粥样硬化进程中,辛伐他汀、氨氯地平均可以通过下调血红素加氧酶／一氧化碳系统而延缓动脉粥样硬化进程。     

Papain-hydrolyzed pork meat reduces serum cholesterol level and premature atherosclerosis in dietary-induced hypercholesterolemic rabbits

The effects of the low-molecular-weight fraction of papain-hydrolyzed pork meat (LMF) on the plasma cholesterol level and the generation of atherosclerosis were studied in rabbits fed a cholesterol-enriched diet. In LMF-fed rabbits, the plasma and liver cholesterol concentrations were both significantly lower (p<0.0 1) than in rabbits fed untreated pork meat (PM). Similarly, the cholesterol concentrations of the chylomicron and VLDL fractions were significantly lower in LMF-fed rabbits than in rabbits fed PM. Deposition of lipid in transverse sections of the aortic arch was significantly less in rabbits fed LMF than in those fed PM. Electron microscopic studies revealed preventive effects against premature atherosclerotic lesions in the aorta of rabbits fed LME These results indicate that LMF has a hypocholesterolemic action and preventive effects against premature atherosclerosis.     

Metabolic benefits of annatto-extracted tocotrienol on glucose homeostasis,inflammation, and gut microbiome

Emerging evidence suggests that the gut microbiome plays an important role in the pathophysiology of both obesity and type 2 diabetes mellitus. We previously reported that dietary annatto-extracted tocotrienol exerts beneficial effects by modulating inflammatory responses in mice fed a high-fat diet (HFD). The purpose of this study was to test the hypothesis that tocotrienol supplementation when combined with an HFD would result in an altered gut microbiota composition. For 14 weeks, forty-eight male C57BL/6J mice were assigned to 4 groups—low-fat diet, HFD, HFD supplemented with annatto-extracted tocotrienol at 800 mg/kg diet (AT), and HFD supplemented with metformin at 200 mg/kg diet. Glucose homeostasis was assessed by glucose and insulin tolerance tests, serum and pancreas insulin levels, and histological assessments of insulin and glucagon in pancreatic tissue. The concentrations of adipokines were measured in white adipose tissues. For the gut microbiome analysis, cecal content was collected, DNA was extracted, and 16S rRNA gene sequencing was performed. AT supplementation improved glucose homeostasis and lowered resistin, leptin, and interleukin-6 levels in white adipose tissue. Relative to the HFD group, AT-supplemented mice showed a decrease in the Firmicutes to Bacteroidetes ratio and had a lower abundance of Ruminococcus lactaris, Dorea longicatena, and Lachnospiraceae family. The relative abundance of Akkermansia muciniphila was increased in the AT group compared to the low-fat diet group. The association between the metabolic improvements and the identified bacterial taxa suggests a potential metabolic modulation caused by AT supplementation through the gut microbiota composition in mice fed an HFD.     

Intermittent Fasting Ameliorated High-Fat Diet-Induced Memory Impairment in Rats via Reducing Oxidative Stress and Glial Fibrillary Acidic Protein Expression in Brain

Intermittent fasting (IF) plays an important role in the protection against metabolic syndrome-induced memory defects. This study aimed to assess the protective effects of both prophylactic and curative IF against high-fat diet (HFD)-induced memory defects in rats. The control group received a normal diet; the second group received a HFD; the third group was fed a HFD for 12 weeks and subjected to IF during the last four weeks (curative IF); the fourth group was fed a HFD and subjected to IF simultaneously (prophylactic IF). A high-fat diet significantly increased body weight, serum lipids levels, malondialdehyde (MDA) concentration, glial fibrillary acidic protein (GFAP) and H score in brain tissue and altered memory performance. In addition, it significantly decreased reduced glutathione (GSH) concentration in brain tissue and viability and thickness of pyramidal and hippocampus granular cell layers. However, both types of IF significantly decreased body weight, serum lipids, GFAP protein expression and H score and MDA concentration in brain tissue, and improved memory performance, while it significantly increased GSH concentration in brain tissue, viability, and thickness of pyramidal and granular cell layers of the hippocampus. This study indicated that IF ameliorated HFD-induced memory disturbance and brain tissue damage and the prophylactic IF was more potent than curative IF.     

微量元素硒对动脉粥样硬化家兔内皮素的影响

用放免分析方法，对服Ｓｅ的动脉粥样硬化（ＡＳ）家兔血浆内皮素（ＥＴ）水平进行测定。结果表明，Ｓｅ组家兔血浆ＥＴ水平明显低于对照组，同时血清胆固醇（Ｃｈ）、低密度脂蛋白（ＬＤＬ）及过氧化脂质（ＬＰＯ）含量降低，高密度脂蛋白（ＨＤＬ）明显增高，全血谷胱甘肽过氧化物酶（ＧＳＨ－Ｐｘ）和血清超氧化物歧化酶（ＳＯＤ）活力也明显提高。提示，Ｓｅ可通过抗氧化作用保护内皮细胞免遭过氧化损伤，减少ＥＴ释放，抑制ＡＳ形成和发展。     

The effects of berberine on hyperhomocysteinemia and hyperlipidemia in rats fed with a long-term high-fat diet

ABSTRACT: BACKGROUND: The study was undertaken to examine the effects of berberine (BBR) on serum homocysteine, lipids and the aortic lesion in Sprague-Dawley (SD) rats fed with a long-term high-fat diet (HFD). METHODS: Healthy male SD rats weighing 190-210 g received randomly standard diet or a high-fat diet for 24 weeks. After 8 weeks of feeding, rats fed with HFD were randomized to receive berberine (200 mg * kg-1 * day-1) or vehicle by gavage for 16 weeks. After overnight fasting, all rats were sacrificed and total blood samples were also collected for determinant of fasting serum homocysteine (Hcy), total cholesterol (TC) and low density lipoprotein cholesterol (LDL-c) levels. The aorta was stained with hematoxylin and eosin (HE) and Sudan Sha to evaluate aortic lesion. The livers were dissected out and snap-frozen in liquid nitrogen for hepatic TC content and molecular analysis. 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), Lipoprotein receptors and apolipoproteins gene expression in the liver were determined by real-time PCR. RESULTS: Intragastrical administration with berberine for 16 weeks lowered serum Hcy in rats fed with a high-fat diet. In parallel, it also decreased body weight and improved serum TC and LDL-c. Berberine also tended to decrease hepatic cholesterol. Consistently, berberine also upregulated LDL receptor (LDLR) mRNA level and suppressed HMGR gene expression. Meanwhile, upon berberine-treated rats, there was a significant increase in apolipoprotein E (apoE) mRNA, but no change in apoAI and scavenger receptor (SR) mRNA in the liver. Further, no atherosclerotic lesions were developed in berberine-treated rats for 16 weeks. CONCLUSION: Berberine can counteract HFD-elicited hyperhomocysteinemia and hyperlipidemia partially via upregulating LDLR and apoE mRNA levels and suppressing HMGR gene expression.