Salicornia Extract Ameliorates Salt‐Induced Aggravation of Nonalcoholic Fatty Liver Disease in Obese Mice Fed a High‐Fat Diet

High‐fat and high‐salt intakes are among the major risks of chronic diseases including obesity, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH). Salicornia is a halophytic plant known to exert antioxidant, antidiabetic, and hypolipidemic effects, and Salicornia‐extracted salt (SS) has been used as a salt substitute. In this study, the effects of SS and purified salt (PS) on the aggravation of NAFLD/NASH were compared. C57BL/6J male mice (8‐wk‐old) were fed a high‐fat diet (HFD) for 6 mo and divided into 3 dietary groups, which were additionally fed HFD, HFD + SS, and HFD + PS for 13 wk. PS induced aggravation of NAFLD/NASH in HFD‐fed mice. Although the actual salt intake was same between the PS and SS groups as 1% of the diet (extrapolated from the World Health Organization [WHO] guideline), SS induced less liver injury and hepatic steatosis compared to PS. The hepatic mRNA expressions of inflammatory cytokines and fibrosis marker were significantly lower in the SS group than the PS group. Oxidative stress is one of the major causes of inflammation in NAFLD/NASH. Results of the component analysis showed that the major polyphenols that exhibited antioxidant activity in the Salicornia water extract were ferulic acid, caffeic acid, and isorhamnetin. These results suggest that even the level of salt intake recommended by WHO can accelerate the progression of liver disease in obese individuals consuming HFD. It is proposed that SS can be a salt substitute for obese individuals who consume HFD.     

Pine needle extract suppresses adiposity via mediating adipogenic gene expressions of white adipose tissue in high fat diet-fed rats

Effect of pine needle extract (PNE) on adiposity was examined through morphologic examination and adipogenic gene expression of white adipose tissue (WAT) in high fat diet (HFD)-fed rats. Four type diets; normal diet (ND), HFD, and diets respectively supplemented with PNE in both ND and HFD, were fed for 8 weeks. The adipose fat mass and the sizes in WAT were significantly lower in PNE-supplemented HFD group than in HFD group. The serum levels of PNE-supplemented HFD group were similar to those of ND group. The supplementation of PNE to HFD markedly increased adiponectin mRNA, but decreased those of leptin and tumor necrosis factor (TNF)-α in WAT, respectively. PNE enhanced glucose uptake of epididymal WAT under insulin stimulation. The results suggest that the beneficial effect of PNE supplementation on adipose fat and serum profiles in HFD-fed rats is partly modulated by adipogenic genes, such as adiponectin, leptin, and TNF-α mRNA in WAT.     

Fermented soy‐powder milk with Lactobacillus plantarum P1201 protects against high‐fat diet‐induced obesity

Fermented soy‐powder milk (FSPM) with Lactobacillus plantarum P1201 contains more conjugated linoleic acid (CLA) and isoflavone aglycones compared with unfermented soy‐powder milk (UFSPM). In this study, the antiobesity effect of FSPM was investigated in a high‐fat diet (HFD)‐induced obesity model. Results showed that FSPM reduced the weight of body, body weight gain, liver and mesenteric white adipose tissue by 10.7%, 17.7%, 32.8% and 24.1%, respectively, compared with the HFD group. Meanwhile, FSPM suppressed the HFD‐induced increase of serum parameters such as total and low‐density lipoprotein, cholesterol, alanine transaminase, glucose and c‐peptide. To investigate how FSPM ameliorated obesity, several lipid metabolism and inflammation‐related genes in liver were analysed. FSPM significantly ameliorated HFD‐induced hepatic steatosis by down‐regulating peroxisome proliferator‐activated receptor gamma, lipoprotein lipase, fatty acid synthase, acetyl CoA carboxylase, adipocyte fatty acid‐binding protein, tumour necrosis factor alpha and interleukin 1 beta. Our results showed FSPM can protect against HFD‐induced obesity.     

Piperine reverses high fat diet-induced hepatic steatosis and insulin resistance in mice

This study examined the effect of piperine on hepatic steatosis and insulin resistance induced in mice by feeding a high-fat diet (HFD) for 13 weeks and elucidated potential underlying molecular mechanisms. Administration of piperine (50 mg/kg body weight) to mice with HFD-induced hepatic steatosis resulted in a significant increase in plasma adiponectin levels. Also, elevated plasma concentrations of insulin and glucose and hepatic lipid levels induced by feeding a HFD were reversed in mice when they were administered piperine. However, piperine did not reduce body weight and other biochemical markers to an extent where they became equal to the levels found in the CD-fed mice. Piperine reversed HFD-induced down-regulation of adiponecitn-AMP-activated protein kinase (AMPK) signalling molecules which play an important role in mediating lipogenesis, fatty acid oxidation and insulin signalling in the livers of mice. The expressions of lipogenic target genes were decreased, whereas the expression of carnitine palmitoyltransferase 1 (CPT1) gene involved in fatty acid oxidation was increased in the livers of the Pin50 group. Piperine significantly decreased the phosphorylation of insulin receptor substrate-1 (IRS-1) compared with the HFD-fed mice. Administration of piperine appeared to reverse preexisting HFD-induced hepatic steatosis and insulin resistance, probably by activation of adiponectin-AMPK signalling in mice.     

Chestnut (Castanea crenata) inner shell extract inhibits development of hepatic steatosis in C57BL/6 mice fed a high-fat diet

The effects of chestnut inner shell extract (CISE) on hepatic steatosis and lipid metabolism in mice fed high-fat diet (HFD) were evaluated. Hepatic triacylglycerol and plasma lipid levels decreased significantly in CISE-administered mice compared to control group. Relative mRNA expression levels for lipogenic genes SREBP-1c, FAS, ACCs, ACAT, and HMG-CoA were significantly decreased in CISE-administered mice (P < 0.05). CISE suppressed FAS and HMG-CoA reductase activity and increased CPT activity. To determine the active compound of CISE, the fractionation of CISE have conducted and resulted in the isolation of scoparone and scopoletin, as main compounds contained in CISE. Based on these results, we speculate that the inhibitory effect on hepatic steatosis of CISE containing scoparone and scopoletin may be the result of suppression of lipid synthesis and the acceleration of fatty acid oxidation in mice fed HFD, suggesting that CISE may be beneficial in preventing hepatic steatosis.     

大豆不溶性膳食纤维对高脂饮食诱导小鼠肥胖的预防作用

目的:研究大豆不溶性膳食纤维(Soybean insoluble dietary fiber,SIDF)对高脂饮食(High fat diet,HFD)诱导小鼠肥胖的预防作用及其机理。方法:将50只C57BL/6J小鼠随机分为正常饮食对照组(Normal diet,ND)、高脂饮食对照组(HFD)和大豆不溶性膳食纤维低(Low-dose soybean insoluble dietary fiber,LSIDF)(250 mg/kg BW/d)、中(Middle-dose soybean insoluble dietary fiber,MSIDF)(500 mg/kg BW/d)、高剂量组(High-dose soybean insoluble dietary fiber,HSIDF)(1 g/kg BW/d),ND组饲喂正常饲料,其余各组饲喂高脂饲料,连续喂养20周。实验结束后统计体质量、肝脏和脂肪湿质量,制作肝脏组织病理切片,测定血清及肝脏脂质水平,实时荧光定量聚合酶链式反应测定小鼠肝脏中脂代谢相关基因表达水平。结果:与HFD组比,SIDF各剂量组可显著减缓小鼠体重增加,降低其血清和肝脏中总胆固醇(Total cholesterol,TC)、甘油三酯(Triglyceride,TG)水平(P<0.05),并且HSIDF组效果优于LSIDF、MSIDF组;小鼠肝脏指数(P<0.05)和脂肪系数(P<0.001)显著降低,其中MSIDF和HSIDF组小鼠腹部脂肪(P<0.001)和肾周脂肪重量(P<0.001)显著减少;HSIDF组显著下调小鼠肝脏中脂肪酸合成酶(Fatty acid synthase,FAS)、二酰甘油酰基转移酶1(Diacylglycerol acyltransferase-1,DGAT1)、二酰甘油酰基转移酶2(Diacylglycerol acyltransferase-2,DGAT2)、硬脂酰辅酶A去饱和酶1(Stearyl-coenzyme A dehydrogenase-1,SCD1)基因表达水平(P<0.05),同时上调过氧化物酶体增殖物激活受体α(Peroxisome proliferators-activated receptor-α,PPARα)、肉毒碱棕榈酰基转移酶1a(Carnitine palmtoyl transferase-1a,CPT1a)基因表达水平(P<0.05)。结论:IDFS对HFD诱导小鼠肥胖具有预防作用,可能与减少脂质合成,加快脂肪酸氧化有关,其可作为一种潜在的膳食补充剂。     

黄大茶水提物改善高脂小鼠脂肪组织的脂肪酸代谢

目的：探究黄大茶水提物对高脂饮食小鼠脂肪组织脂肪酸代谢的调控机制。方法：将5 周龄雄性C57BL/6小鼠随机分为对照组、高脂饮食组、高脂饮食＋2.5%（终质量分数,下同）黄大茶水提取物组、高脂饮食＋0.5%黄大茶水提取物组。饮食干预处理12 周后,测定小鼠体质量、脂肪组织质量,观察脂肪组织形态,并分析脂肪酸代谢关键基因及蛋白表达量等指标。结果：2.5%黄大茶水提物能高度显著降低高脂小鼠体质量及脂肪组织质量（P＜0.001）;减少脂肪组织的脂质沉积;促进SREBP-1C、FAS、ACC、SCD-1等脂肪酸生成相关基因的表达,促进脂肪酸分解相关基因PGC-1α和CPT-1的表达;不同程度激活腺苷酸活化蛋白激酶（adenosine monophosphate activated protein kinase,AMPK）/乙酰辅酶A羧化酶（acetyl CoA-carboxylase,ACC）通路。结论：2.5%黄大茶水提物饮食干预能显著缓解高脂饮食小鼠肥胖和减少脂质沉积,促进脂肪组织脂肪酸合成和氧化分解代谢,此作用与黄大茶水提物激活AMPK/ACC通路相关。     

The effect of chemically‐modified resistant starch,RS type‐4, on body weight and blood lipid profiles of high fat diet‐induced obese mice

This study was conducted to investigate the effects of feeding chemically‐modified resistant starch type‐4 (RS4) of normal (NCS) and high‐amylose corn starch (HACS) on weight gain and plasma and liver lipid profiles of mice fed a high‐fat diet (HFD). The experimental four groups were, respectively, fed following diets: A 40% HFD with NCS, HACS, NCS‐ and HACS‐RS4. A normal diet (ND) group of mice fed the standard diet was also used as control. In order to produce RS4 by chemical modification, corn starches were treated with STMP/STPP. Total RS (TRS) and total dietary fiber (TDF) levels of chemically‐modified NCS were 26.4 and 44.0%, respectively, while TRS and TDF levels in chemically‐modified HACS were 78.1 and 78.5%, respectively. Onset gelatinization temperatures of both modified corn starches clearly shifted to higher temperatures after STMP/STPP treatment. At the end of the diet trial, the mice on the HACS diet decreased body weight gain compared to the NCS‐fed mice. Adding NCS‐ and HACS‐RS4 to the diet significantly reduced the weight gain relative to NCS and HACS groups. Both RS4 diets were effective in improving the lipid profile compared to their respective controls. They significantly reduced the level of total lipid and total cholesterol.     

枯草芽孢杆菌JS01对肥胖小鼠肠道菌群及脂褐质的影响

探究枯草芽孢杆菌JS01对高脂饮食引起的肠道菌群紊乱、肥胖、肝脏脂质沉积及过氧化等是否有积极的治疗作用。以雄性小鼠为实验动物建立肥胖模型组(C～F),并用不同含量的枯草芽孢杆菌JS01饲喂低、中、高干预组(D、E、F)。结果表明：添加枯草芽孢杆菌后,干预组F的体质量显著减轻,干预组E、F的体质量增长率明显降低。高脂饮食使模型对照组C小肠中双歧杆菌含量上升、乳酸杆菌含量下降、肝脏脂肪变性明显且脂褐质含量上升,添菌后使模型干预组(D、E、F)小肠中的大肠杆菌和双歧杆菌含量均下降、乳酸杆菌含量上升、肝脏脂肪变性程度减轻且脂褐质含量降低。枯草芽孢杆菌JS01能改善因高脂饮食引起的肥胖、肠道菌群紊乱、肝脏脂质沉积及过氧化。     

Fatty acid composition of liver and adipose tissue lipids in Wistar rats with fat diet-induced obesity

The influence of dietary fat on the fatty acid composition of liver and adipose tissue lipids was investigated after 4 and 19 weeks of high-fat feeding (50% fat) in comparison to low-fat feeding (3% fat), beginning in the sixth week of age. In rats fed the low-fat diet or an usual pellet diet the fatty pattern of liver triglycerides (TG) was equal to that of adipose tissue, while there were no similarities to the diet. In total liver lipids a constant fatty acid profile was observed, independently of the duration of feeding. High fat feeding results several changes in the fatty acid pattern of liver lipids. While after 4 weeks the fatty acids of liver TG more closely resembled the dietary fatty acids than those of adipose tissue, after 19 weeks of feeding the fatty acid composition of liver TG is comparable with that of adipose tissue. Not all rats fed the high fat diet rendered obese. It could be shown that in rats with higher lipid concentrations in the liver only the fatty acid pattern of liver phospholipids has been altered, while the composition of TG, which are the lipids primarily increased, was not changed.     

虾青素对肝脂代谢与昼夜节律的调节作用

研究虾青素对非酒精性脂肪性肝病（non-alcoholic fatty liver disease,NAFLD）的干预作用及与代谢相关的昼夜节律紊乱的缓解作用。采用高脂/高胆固醇饲喂建立NAFLD小鼠模型和添加虾青素的干预模型。动物实验选用SPF级C57BL/6小鼠,随机分成正常组、高脂模型组和高脂添加虾青素组。采用常规酶联免疫吸附测定法测定血清中甘油三酯、总胆固醇（total cholesterol,TC）、高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDL-C）、低密度脂蛋白胆固醇（low density lipoprotein cholesterol,LDL-C）浓度及谷丙转氨酶（alanine aminotransferase,ALT）、谷草转氨酶（aspartate transaminase,AST）活力等肝损伤指标,苏木精-伊红染色法观察肝组织形态学变化,荧光定量聚合酶链式反应（real-time quantitative polymerase chain reaction,qPCR）检测与肝脂代谢、胆固醇代谢、昼夜节律相关的基因表达及昼夜节律变化。结果显示：与正常组相比,高脂模型组小鼠体质量、肝脏指数、肥胖指数均高度显著增加（P＜0.001）,虾青素干预后肝脏指数、肥胖指数均极显著降低（P＜0.01）。高脂饲喂导致小鼠血脂水平升高（HDL-C除外）,尤其是LDL-C浓度升高明显,而虾青素干预可以有效降低TC和LDL-C浓度,并升高HDL-C浓度,改善脂质的代谢。高脂/高胆固醇饲喂会高度显著升高小鼠血清ALT、AST活力（P＜0.001）,造成肝损伤。与高脂模型组相比,虾青素干预可极显著降低小鼠ALT、AST活力（P＜0.01）,缓解肝脏损伤,并明显改善肝脏脂质代谢关键酶的基因表达,包括脂肪酸合成酶和胆固醇合成关键酶羟甲基戊二酸单酰辅酶A还原酶。同时,虾青素干预也增加了胆固醇7α-羟化酶的表达量,促进胆固醇氧化。虾青素调节上述基因的表达具有昼夜节律性,能够缓解或修正由高脂导致的生物钟节律相关因子时钟昼夜节律调节器及脑和肌肉芳香烃受体核转运体样蛋白1以及肝脏脂质代谢关键基因昼夜节律表达的紊乱。本研究表明虾青素具有改善高脂所致肝代谢紊乱的节律性调节作用。     

Auraptene regulates gene expression involved in lipid metabolism through PPARα activation in diabetic obese mice

Scope: Peroxisome proliferator‐activated receptor‐α (PPARα) is a key regulator of circulating lipid level. Thus, various food‐derived compounds that activate PPARα as agonists have been screened and characterized. Methods and results: We investigated the effects of auraptene, a citrus‐derived compound serving as a PPARα agonist in vitro, on abnormalities in lipid and glucose metabolisms. In high‐fat‐diet (HFD)‐fed KK‐Ay diabetic obese mice, auraptene treatment suppressed hyperlipidemia and triglyceride accumulation in the liver and skeletal muscle, and increased the mRNA expression levels of the PPARα target genes involved in fatty acid oxidation in the liver and skeletal muscle. Moreover, the adipocyte size in the auraptene‐treated mice was significantly smaller than that in the control HFD‐fed mice resulting in the improvement of HFD‐induced hyperglycemia and abnormalities in glucose tolerance. Conclusions: These findings indicate that auraptene activates PPARα also in vivo and its treatment may improve abnormalities in lipid and glucose metabolisms, suggesting that auraptene is a valuable food‐derived compound for managing metabolic disorders.     

Chronic dietary intake of quercetin alleviates hepatic fat accumulation associated with consumption of a Western-style diet in C57/BL6J mice

Scope: To determine the effect of consumption of a quercetin‐rich diet on obesity and dysregulated hepatic gene expression. Methods and results: C56BL/6J mice were fed for 20 wk on AIN93G (control) or a Western diet high in fat, cholesterol and sucrose, both with or without 0.05% quercetin. Triglyceride levels in plasma, thiobarbituric acid‐reactive substances (oxidative stress marker) and glutathione levels and peroxisome proliferator‐activated receptor α expression in livers of mice fed with the Western diet were all improved after 8 wk feeding with quercetin. After 20 wk, further reductions of visceral and liver fat accumulation and improved hyperglycemia, hyperinsulinemia, dyslipidemia and plasma adiponectin and TNFα levels in these mice fed with quercetin were observed. The expression of hepatic genes related to steatosis, such as peroxisome proliferator‐activated receptor γ and sterol regulatory element‐binding protein‐1c was also normalized by quercetin. In mice fed with the control diet, quercetin did not affect body weight but reduces the plasma TNFα and hepatic thiobarbituric acid‐reactive substance levels. Conclusion: In mice fed with a Western diet, chronic dietary intake of quercetin reduces liver fat accumulation and improves systemic parameters related to metabolic syndrome, probably mainly through decreasing oxidative stress and reducing PPARα expression, and the subsequent reduced expression in the liver of genes related to steatosis.     

RS4型抗性淀粉对高脂诱导肥胖小鼠脂质代谢相关基因表达的影响

目的：观察不同RS4型抗性淀粉对小鼠脂质代谢及相关基因表达的影响,探讨抗性淀粉干预脂质代谢的机制。方法：选用年龄和体质量合适的雄性C57BL/6J小鼠,分别饲喂含有羟丙基交联、交联酯化、柠檬酸乙酰化甘薯淀粉3 种RS4型抗性淀粉和甘薯原淀粉的高脂饲料12 周。12 周后,测定小鼠血清指标、体质量及观察小鼠肝脏组织形态变化;并采用实时荧光定量聚合酶链式反应技术检测各组小鼠肝组织中脂肪酸合成酶（fatty acid synthese,FAS）、固醇调节元件结合蛋白-1c（sterol regulatory element binding protein-1c,SREBP-1c）、3-羟基-3-甲基戊二酰辅酶A还原酶（3-hydroxy-3-methylglutary coenzyme a reductase,HMGCR）的mRNA表达水平。结果：饲喂添加3 种RS4型抗性淀粉的高脂饲料后,高脂诱导雄性C57BL/6J肥胖小鼠体质量、血清甘油三酯水平明显降低,肝细胞脂肪变性程度明显减轻、肝脏组织中SREBP-1c mRNA表达水平明显下调;添加柠檬酸乙酰化甘薯淀粉对FAS、SREBP-1c、HMGCR 的mRNA表达水平均有不同程度的下调。结论：柠檬酸乙酰化甘薯淀粉等RS4型抗性淀粉可对高脂诱导雄性C57BL/6J肥胖小鼠的脂质代谢起到一定的干预作用,并可下调其肝脏组织中SREBP-1c mRNA等基因的表达。     

Cornus officinalis vinegar reduces body weight and attenuates hepatic steatosis in mouse model of nonalcoholic fatty liver disease

This study aimed to determine the main bioactive components of Cornus officinalis vinegar (COV) and assess the effects of COV on the body weight (BW) and hepatic steatosis in a nonalcoholic fatty liver disease (NAFLD) mouse model. Seven-week-old KM female mice were divided into five treatment groups: (1) Normal control (NC) group, (2) high fat diet (HFD) group, (3) low concentration treatment group (3.5% COV), (4) medium concentration treatment group (5.0% COV), and (5) high concentration treatment group (6.5% COV). Mice in the NC group were fed with a normal chow diet, and those in the other four groups were fed with a HFD known for causing obesity for 10 weeks. Then, mice in the three COV treatment groups were orally administered with COV once a day for 6 weeks. Results showed that the contents of loganin and morroniside in COV reached 16.82 and 51.17 µg/ml, respectively, and COV also contained multiple organic acids. COV significantly reduced BW, abdominal fat weight, liver weight, and the levels of glucose, triglyceride, and low-density lipoprotein cholesterol of serum and increased the levels of high-density lipoprotein cholesterol of serum (p < 0.05). COV also improved the liver function and anti-oxidant activity of liver (p < 0.05). COV treatments increased the interleukin-10 expression and reduced the tumor necrosis factor-α expression in the liver tissue of NAFLD mice (p < 0.05). Histopathological observation revealed that COV suppressed hepatic lipid accumulation and steatosis. The results suggest that COV may contribute to the alleviation of NAFLD and obesity.     

黑茶桑叶固体饮料对高脂饮食小鼠的减肥作用

该研究旨在探究以黑茶和桑叶提取物为主的固体饮料对高脂饮食（HFD）小鼠的减肥作用。通过饲喂高脂饲料建立肥胖模型,随机分为模型组、阳性药组、低（385.0 mg/kg体质量）、中（765.0 mg/kg体质量）、高（1147.5 mg/kg体质量）剂量固体饮料组,灌胃6周后检测小鼠相关生化指标,观察其肝脏及脂肪组织切片,并进行肠道菌群测序。结果显示,固体饮料组均能减少模型组小鼠60%以上的体质量增量和40%以上的脂肪湿质量;改善HFD小鼠的肝脏脂滴聚集、脂肪变性的问题,缓解脂肪组织细胞膨大的情况;同时,该固体饮料能降低HFD小鼠肠道内厚壁菌门（Firmicutes）与拟杆菌门（Bacteroidetes）比值（F/B）,提高部分有益菌的丰度。说明该黑茶固体饮料对HFD诱导的肥胖模型小鼠能起到显著减肥作用,且高剂量组优于中低剂量组。     

The Beneficial Effect of Propolis on Fat Accumulation and Lipid Metabolism in Rats Fed a High-Fat Diet

ABSTRACT:  This study examined whether propolis, which had many biological activities, affected body fat and lipid metabolism. Four-week-old Wistar rats were fed a control or propolis diet for 8 wk. The control group was fed a high-fat diet, the low and the high group were fed a high-fat diet supplemented with 0.5% (w/w) and 0.05% (w/w) propolis, respectively. The weight of total white adipose tissue of the high group was lower than that of the control group. The level of PPARγ protein in the adipose tissues of the high group was significantly lower than that of the control group. In plasma and the liver, the high group showed a significantly reduced level of cholesterol and triglyceride compared to the control group. The liver PPARα protein level of the high group was significantly higher than that of the control group. The liver HMG-CoA reductase protein in the high group was also significantly lower than that in the control group. Results from rats on an olive oil loading test were used to investigate whether propolis inhibited triglyceride absorption. The serum triglyceride level of the group, which received propolis corresponding to the daily dose of the high group, was significantly lower than that of the control group. It is possible that the administration of propolis improves the accumulation of body fat and dyslipidemia via the change of the expression of proteins involved in adipose depot and lipid metabolism.     

Hepatic steatosis by dietary-conjugated linoleic acid is accompanied by accumulation of diacylglycerol and increased membrane-associated protein kinase C ε in mice

Scope : Conjugated linoleic acid reduces weight gain and adipose mass while inducing liver enlargement, hepatic steatosis, and insulin resistance in mice. The objective of this study was to determine if hepatic steatosis induced by conjugated linoleic acid would predict for hepatic diacylglycerol accumulation, increased membrane‐associated protein kinase C ε, and hyperglycemia. Methods and results : Six‐wk‐old C57Bl/6 male mice were fed a high‐saturated fat diet for 3 wk and were then randomized to high‐saturated fat diet with or without conjugated linoleic acid (1.5% wt). Following a 6‐wk intervention, hepatic triacylglycerol, diacylglycerol, membrane‐associated protein kinase C ε, and gluconeogenic gene expression were determined. Fasting glucose was determined at baseline and at the end of the study. Conjugated linoleic acid increased hepatic triacylglycerol and diacylglycerol concentration in association with increased membrane‐associated protein kinase C ε. Diacylglycerol concentration proved to be a better predictor than triacylglycerol concentration for the change from baseline in fasting glucose concentration and final insulin concentration. The increase in diacylglycerol concentration was also associated with increased hepatic gluconeogenic gene expression in conjugated linoleic acid‐treated animals. Conclusion : Our data suggest that conjugated linoleic acid can initiate the pathophysiology responsible for hepatic insulin resistance. Additional studies are needed to determine if the accumulation of hepatic diacylglycerol by conjugated linoleic acid leads to hepatic insulin resistance.     

荞麦粉对高脂膳食大鼠脂代谢的影响

本文研究了荞麦粉(buckwheat,BW)对高脂膳食大鼠脂代谢的影响。将50只成年Wistar雄性大鼠随机分为基础对照组、高脂模型组、荞麦粉低、中、高剂量组(1、5、10 g/kg·d),每天喂食一次,饲喂30 d后腹主动脉取血,取出肝脏、肾周及睾丸附近脂肪,分别测定血清和肝脏中的总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C)的水平,并观察肝脏病理切片。结果表明,与高脂膳食组相比,荞麦剂量组大鼠体重和食物摄入量都明显减少,肝重和脂肪重及其指数也明显降低,血清和肝脏中TC、TG、LDL-C的浓度降低,HDL-C的浓度升高。肝脏光镜结构表明,荞麦剂量组的肝脏脂肪变性均减轻,其中荞麦粉高剂量作用最为明显。说明荞麦粉干预高脂膳食,可起到降血脂、改善肝脏脂代谢、保护肝脏的作用,同时能够减少相关疾病的发生。